/* Auto-generated by @arclux/prism — do not edit manually */

/* Design Tokens */
:root {

  color-scheme: dark;

  --bg-deep: rgb(3, 3, 7);
  --bg-surface: rgb(10, 10, 15);
  --bg-base: rgb(10, 10, 15);
  --bg-card: rgb(13, 13, 18);
  --bg-elevated: rgb(17, 17, 22);

  --text-primary: rgb(232, 232, 236);
  --text-secondary: rgb(138, 138, 150);
  --text-muted: rgb(124, 124, 137);
  --text-ghost: rgb(107, 107, 128);

  --border-subtle: rgb(24, 24, 30);
  --border-default: rgb(34, 34, 41);
  --border-bright: rgb(51, 51, 64);

  --accent-primary: rgb(77, 126, 247);
  --accent-secondary: rgb(139, 92, 246);
  --accent-primary-rgb: 77, 126, 247;
  --accent-secondary-rgb: 139, 92, 246;
  --text-primary-rgb: 232, 232, 236;
  --text-muted-rgb: 124, 124, 137;
  --color-error-rgb: 239, 68, 68;
  --white-rgb: 255, 255, 255;
  --black-rgb: 0, 0, 0;

  --accent-primary-subtle: rgba(var(--accent-primary-rgb), 0.06);
  --accent-primary-border: rgba(var(--accent-primary-rgb), 0.12);
  --accent-primary-glow: rgba(var(--accent-primary-rgb), 0.2);
  --accent-primary-ring: rgba(var(--accent-primary-rgb), 0.15);
  --accent-secondary-subtle: rgba(var(--accent-secondary-rgb), 0.06);
  --accent-secondary-border: rgba(var(--accent-secondary-rgb), 0.12);
  --accent-secondary-glow: rgba(var(--accent-secondary-rgb), 0.2);

  --color-success: rgb(52, 211, 153);
  --color-success-rgb: 52, 211, 153;
  --color-error: rgb(239, 68, 68);
  --color-error-subtle: rgba(239, 68, 68, 0.1);
  --color-warning: rgb(245, 158, 11);
  --color-warning-rgb: 245, 158, 11;
  --color-warning-subtle: rgba(245, 158, 11, 0.1);
  --color-info: rgb(59, 130, 246);
  --color-info-rgb: 59, 130, 246;
  --color-info-subtle: rgba(59, 130, 246, 0.1);

  --shadow-xs: 0 1px 2px rgba(0, 0, 0, 0.2);
  --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.2), 0 1px 2px rgba(0, 0, 0, 0.15);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.25), 0 2px 4px rgba(0, 0, 0, 0.15);
  --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.3), 0 4px 8px rgba(0, 0, 0, 0.15);
  --shadow-xl: 0 16px 48px rgba(0, 0, 0, 0.35), 0 8px 16px rgba(0, 0, 0, 0.15);
  --shadow-overlay: 0 8px 32px rgba(0, 0, 0, 0.4);
  --shadow-inset: inset 0 1px 3px rgba(0, 0, 0, 0.25);

  --z-base: 0;
  --z-dropdown: 1000;
  --z-tooltip: 1100;
  --z-overlay: 1200;
  --z-modal: 1300;
  --z-toast: 1400;
  --z-max: 9999;

  --breakpoint-xs: 480px;
  --breakpoint-sm: 640px;
  --breakpoint-md: 768px;
  --breakpoint-lg: 1024px;
  --breakpoint-xl: 1280px;
  --breakpoint-2xl: 1536px;

  --opacity-disabled: 0.5;
  --opacity-muted: 0.6;
  --opacity-hover: 0.8;
  --opacity-visible: 1;

  --font-body: 'Host Grotesk', system-ui, sans-serif;
  --font-accent: 'Tektur', system-ui, sans-serif;
  --font-mono: 'JetBrains Mono', ui-monospace, monospace;

  --text-xs: 12px;
  --text-sm: 16px;
  --text-md: 17px;
  --text-lg: clamp(18px, 1.5vw, 20px);
  --text-xl: clamp(22px, 2.5vw, 26px);
  --text-2xl: clamp(28px, 3vw, 36px);
  --text-3xl: clamp(36px, 5vw, 52px);

  --display-xl-size: var(--text-3xl);
  --display-xl-weight: 500;
  --display-xl-spacing: -1px;
  --heading-size: var(--text-xl);
  --heading-weight: 500;
  --heading-lh: 1.2;
  --body-size: var(--text-md);
  --body-weight: 500;
  --body-lh: 1.7;
  --wordmark-size: clamp(20px, 2.5vw, 28px);
  --wordmark-weight: 500;
  --wordmark-spacing: clamp(8px, 1.2vw, 14px);
  --section-title-size: var(--text-xs);
  --section-title-weight: 600;
  --section-title-spacing: 4px;
  --ui-accent-size: 16px;
  --ui-accent-weight: 600;
  --ui-accent-spacing: 1px;
  --code-size: 14px;
  --code-lh: 1.8;
  --label-inline-size: var(--text-xs);
  --label-inline-spacing: 3px;

  --touch-min: 24px;
  --touch-pad: 4px;

  --space-xs: 4px;
  --space-sm: 8px;
  --space-md: 16px;
  --space-lg: 24px;
  --space-xl: 40px;
  --space-2xl: 64px;
  --space-3xl: 96px;
  --space-4xl: 128px;

  --radius-sm: 4px;
  --radius-md: 10px;
  --radius-lg: 14px;
  --radius-xl: 20px;
  --radius-full: 9999px;

  --transition-fast: 120ms ease;
  --transition-base: 200ms ease;
  --transition-slow: 400ms ease;

  --ease-out-expo: cubic-bezier(0.16, 1, 0.3, 1);
  --ease-in-out: cubic-bezier(0.4, 0, 0.2, 1);
  --duration-enter: 500ms;
  --duration-exit: 300ms;

  --gradient-display-text: linear-gradient(135deg, rgb(232, 232, 236) 0%, rgb(124, 124, 137) 100%);
  --gradient-accent-text: linear-gradient(90deg, var(--accent-primary), var(--accent-secondary));
  --gradient-divider: linear-gradient(90deg, transparent, rgb(24, 24, 30), transparent);
  --gradient-divider-glow: linear-gradient(90deg, transparent, rgba(var(--accent-primary-rgb),0.2), rgba(var(--accent-secondary-rgb),0.12), transparent);
  --gradient-page-ambient: radial-gradient(ellipse, rgba(255, 255, 255,0.015) 0%, transparent 70%);

  --glow-white: 0 0 6px rgba(var(--text-primary-rgb),0.6), 0 0 18px rgba(var(--text-primary-rgb),0.25), 0 0 40px rgba(var(--text-primary-rgb),0.1);
  --glow-primary: 0 0 8px rgba(var(--accent-primary-rgb),0.9), 0 0 20px rgba(var(--accent-primary-rgb),0.5), 0 0 44px rgba(var(--accent-primary-rgb),0.25), 0 0 80px rgba(var(--accent-primary-rgb),0.1);
  --glow-secondary: 0 0 8px rgba(var(--accent-secondary-rgb),0.9), 0 0 20px rgba(var(--accent-secondary-rgb),0.4), 0 0 40px rgba(var(--accent-secondary-rgb),0.15);

  --glow-line-white: linear-gradient(90deg, transparent, rgba(var(--text-primary-rgb),0.35), transparent);
  --glow-line-blue: linear-gradient(90deg, transparent, rgba(var(--accent-primary-rgb),0.7), transparent);
  --glow-line-gradient: linear-gradient(90deg, transparent, var(--accent-primary), var(--accent-secondary), transparent);

  --glow-hover: 0 0 12px rgba(var(--accent-primary-rgb), 0.15);
  --glow-card-hover: 0 0 20px rgba(var(--accent-primary-rgb),0.08), 0 0 40px rgba(var(--accent-secondary-rgb),0.04);
  --gradient-border-glow: linear-gradient(135deg, rgba(var(--accent-primary-rgb),0.15), rgba(var(--accent-secondary-rgb),0.1), rgba(var(--accent-primary-rgb),0.05));
  --gradient-ambient: radial-gradient(circle at 15% 85%, rgba(var(--accent-primary-rgb),0.04) 0%, transparent 50%),
                      radial-gradient(circle at 85% 15%, rgba(var(--accent-secondary-rgb),0.03) 0%, transparent 50%);

  --focus-ring: 0 0 0 1px rgba(var(--accent-primary-rgb),0.25);
  --focus-glow: 0 0 0 1px rgba(var(--accent-primary-rgb),0.2), 0 0 6px rgba(var(--accent-primary-rgb),0.35), 0 0 16px rgba(var(--accent-primary-rgb),0.2), 0 0 40px rgba(var(--accent-secondary-rgb),0.12);

  --max-width: 1120px;
  --max-width-sm: 720px;
  --nav-height: 64px;

  --bg-hover: rgba(255, 255, 255, 0.04);
  --overlay-backdrop: rgba(0, 0, 0, 0.6);

  /* ── Semantic: Interactive ── */
  --interactive: var(--accent-primary);
  --interactive-rgb: var(--accent-primary-rgb);
  --interactive-hover: var(--glow-hover);
  --interactive-active: var(--glow-primary);
  --interactive-focus: var(--focus-glow);
  --interactive-focus-ring: var(--focus-ring);
  --interactive-muted: var(--text-ghost);

  /* ── Semantic: Surface ── */
  --surface-base: var(--bg-deep);
  --surface-primary: var(--bg-surface);
  --surface-raised: var(--bg-card);
  --surface-overlay: var(--bg-elevated);
  --surface-hover: var(--bg-hover);

  /* ── Semantic: Divider ── */
  --divider: var(--border-subtle);
  --divider-glow: var(--glow-line-gradient);

  /* ── Semantic: Feedback composites ── */
  --feedback-error-subtle: var(--color-error-subtle);
  --feedback-error-border: rgba(var(--color-error-rgb), 0.2);
  --feedback-error-glow: 0 0 12px rgba(var(--color-error-rgb), 0.15);
  --feedback-success-subtle: rgba(var(--color-success-rgb), 0.1);
  --feedback-success-border: rgba(var(--color-success-rgb), 0.2);
  --feedback-success-glow: 0 0 12px rgba(var(--color-success-rgb), 0.15);
  --feedback-warning-subtle: var(--color-warning-subtle);
  --feedback-warning-border: rgba(var(--color-warning-rgb), 0.2);
  --feedback-warning-glow: 0 0 12px rgba(var(--color-warning-rgb), 0.15);
  --feedback-info-subtle: var(--color-info-subtle);
  --feedback-info-border: rgba(var(--color-info-rgb), 0.2);
  --feedback-info-glow: 0 0 12px rgba(var(--color-info-rgb), 0.15);


}

/* arc-aspect-ratio */
.arc-aspect-ratio { display: block; }

      .arc-aspect-ratio .aspect-ratio {
        position: relative;
        width: 100%;
        overflow: hidden;
        border-radius: var(--radius-md);
      }

      .arc-aspect-ratio .aspect-ratio__inner {
        width: 100%;
        height: 100%;
      }

      ::slotted(*) {
        width: 100%;
        height: 100%;
        object-fit: cover;
        display: block;
      }

/* arc-avatar-group */
.arc-avatar-group { display: inline-flex; }

      .arc-avatar-group .group {
        display: flex;
        align-items: center;
      }

      ::slotted(*) {
        position: relative;
        box-sizing: border-box;
        box-shadow: 0 0 0 3px var(--surface-base);
        border-radius: var(--radius-full);
        transition: transform var(--transition-fast), box-shadow var(--transition-fast);
      }

      ::slotted(:hover) {
        transform: translateY(-2px) scale(1.08);
        z-index: 100 !important;
        box-shadow: 0 0 0 3px var(--surface-base), 0 4px 12px rgba(0, 0, 0, 0.3);
      }

      .arc-avatar-group .group__overflow {
        display: inline-flex;
        align-items: center;
        justify-content: center;
        font-family: var(--font-accent);
        font-weight: 600;
        font-size: var(--text-sm);
        letter-spacing: 0.5px;
        color: var(--text-ghost);
        user-select: none;
        padding-left: var(--space-sm);
      }

      .arc-avatar-group[data-overlap="sm"] .group__overflow { padding-left: var(--space-xs); }
      .arc-avatar-group[data-overlap="lg"] .group__overflow { padding-left: var(--space-md); }

      @media (prefers-reduced-motion: reduce) {
        .arc-avatar-group *,
        .arc-avatar-group *::before,
        .arc-avatar-group *::after {
          animation-duration: 0.01ms !important;
          animation-iteration-count: 1 !important;
          transition-duration: 0.01ms !important;
        }
      }

/* arc-avatar */
.arc-avatar { display: inline-flex; position: relative; }

      .arc-avatar .avatar {
        display: inline-flex;
        align-items: center;
        justify-content: center;
        border-radius: var(--radius-full);
        border: 1px solid var(--border-default);
        overflow: hidden;
        background: var(--surface-overlay);
        transition: border-color var(--transition-base), box-shadow var(--transition-base), transform var(--transition-base);
        position: relative;
      }

      .arc-avatar .avatar:hover {
        border-color: var(--border-bright);
        box-shadow: var(--interactive-hover);
        transform: scale(1.05);
      }

      .arc-avatar[data-size="sm"] .avatar { width: 32px; height: 32px; }
      .arc-avatar[data-size="md"] .avatar { width: 40px; height: 40px; }
      .arc-avatar[data-size="lg"] .avatar { width: 56px; height: 56px; }

      .arc-avatar .avatar__img {
        width: 100%;
        height: 100%;
        object-fit: cover;
        border-radius: var(--radius-full);
        opacity: 0;
        transition: opacity var(--transition-slow);
      }

      .arc-avatar .avatar__img.loaded { opacity: 1; }

      .arc-avatar .avatar__shimmer {
        position: absolute;
        inset: 0;
        background: linear-gradient(
          90deg,
          var(--surface-overlay) 25%,
          var(--border-subtle) 37%,
          var(--surface-overlay) 63%
        );
        background-size: 200% 100%;
        animation: avatar-shimmer 1.8s ease-in-out infinite;
        border-radius: inherit;
        transition: opacity var(--transition-slow);
      }

      .arc-avatar .avatar__shimmer--hidden { opacity: 0; pointer-events: none; }

      @keyframes avatar-shimmer {
        0%   { background-position: -200% 0; }
        100% { background-position: 200% 0; }
      }

      @keyframes avatar-pulse {
        0%, 100% { opacity: 1; }
        50%      { opacity: 0.7; }
      }

      .arc-avatar .avatar__initials {
        font-family: var(--font-accent);
        font-weight: 600;
        color: var(--text-primary);
        text-transform: uppercase;
        user-select: none;
      }

      /* Shape variants */
      .arc-avatar[data-shape="square"] .avatar,
      .arc-avatar[data-shape="square"] .avatar__img { border-radius: var(--radius-md); }
      .arc-avatar[data-shape="rounded"] .avatar,
      .arc-avatar[data-shape="rounded"] .avatar__img { border-radius: var(--radius-lg); }

      .arc-avatar[data-size="sm"] .avatar__initials { font-size: var(--text-xs); }
      .arc-avatar[data-size="md"] .avatar__initials { font-size: var(--text-sm); }
      .arc-avatar[data-size="lg"] .avatar__initials { font-size: var(--text-lg); }

      /* Status indicator */
      .arc-avatar .avatar__status {
        position: absolute;
        bottom: 0;
        right: 0;
        width: 10px;
        height: 10px;
        border-radius: var(--radius-full);
        border: 2px solid var(--surface-base);
        box-sizing: border-box;
      }

      .arc-avatar[data-size="sm"] .avatar__status { width: 8px; height: 8px; }
      .arc-avatar[data-size="lg"] .avatar__status { width: 14px; height: 14px; border-width: 3px; }

      .arc-avatar[data-status="online"] .avatar__status {
        background: var(--color-success);
        animation: avatar-pulse 2s ease-in-out infinite;
      }
      .arc-avatar[data-status="offline"] .avatar__status { background: var(--text-ghost); }
      .arc-avatar[data-status="busy"] .avatar__status { background: var(--color-error); }
      .arc-avatar[data-status="away"] .avatar__status { background: var(--color-warning); }

      @media (prefers-reduced-motion: reduce) {
        .arc-avatar .avatar__shimmer { animation: none; }
        .arc-avatar .avatar__img { transition: none; }
        .arc-avatar .avatar { transition: border-color var(--transition-base), box-shadow var(--transition-base); }
        .arc-avatar .avatar:hover { transform: none; }
        .arc-avatar[data-status="online"] .avatar__status { animation: none; }
      }

/* arc-card */
.arc-card { display: block; }

      .arc-card .card { height: 100%; }

      /* Suppress hover effect when no href and not interactive */
      .arc-card(:not([href]):not([interactive])) .card:hover {
        background: var(--border-subtle);
      }
      .arc-card(:not([href]):not([interactive])) .card:hover .card__inner {
        box-shadow: none;
      }

      .arc-card[interactive] .card { cursor: pointer; }

      .arc-card .card__inner {
        padding: var(--space-lg);
      }

      /* Padding variants */
      .arc-card[data-padding="none"] .card__inner { padding: 0; }
      .arc-card[data-padding="sm"] .card__inner { padding: var(--space-sm); }
      .arc-card[data-padding="lg"] .card__inner { padding: var(--space-xl); }

      .arc-card .card__body {
        flex: 1;
      }

      .arc-card .card__footer {
        margin-top: var(--space-md);
        position: relative;
      }

      .arc-card .card__footer::before {
        content: '';
        position: absolute;
        top: calc(-1 * var(--space-md) / 2);
        left: var(--space-md);
        right: var(--space-md);
        height: 1px;
        background: var(--divider-glow);
        opacity: 0.5;
      }

      .arc-card .card__footer--empty {
        display: none;
      }

      .arc-card .card__footer--empty::before {
        display: none;
      }

      @media (max-width: 768px) { /* --breakpoint-md */
        .arc-card .card__inner { padding: var(--space-lg) var(--space-md); }
      }

      @media (prefers-reduced-motion: reduce) {
        .arc-card *,
        .arc-card *::before,
        .arc-card *::after {
          animation-duration: 0.01ms !important;
          animation-iteration-count: 1 !important;
          transition-duration: 0.01ms !important;
        }
      }

/* arc-color-swatch */
.arc-color-swatch { display: inline-flex; }

      .arc-color-swatch .swatch {
        display: flex;
        flex-direction: column;
        align-items: center;
        gap: var(--space-sm);
      }

      .arc-color-swatch .swatch__color {
        border-radius: var(--radius-md);
        border: 1px solid var(--border-default);
        transition: border-color var(--transition-base), box-shadow var(--transition-base);
      }

      .arc-color-swatch .swatch__color:hover {
        border-color: var(--border-bright);
        box-shadow: 0 0 12px rgba(var(--accent-primary-rgb), 0.1);
      }

      .arc-color-swatch[data-size="sm"] .swatch__color { width: 32px; height: 32px; border-radius: var(--radius-sm); }
      .arc-color-swatch[data-size="md"] .swatch__color { width: 48px; height: 48px; }
      .arc-color-swatch[data-size="lg"] .swatch__color { width: 64px; height: 64px; border-radius: var(--radius-lg); }

      .arc-color-swatch .swatch__label {
        font-family: var(--font-mono);
        font-size: var(--text-sm);
        color: var(--text-muted);
        text-align: center;
        max-width: 80px;
        overflow: hidden;
        text-overflow: ellipsis;
        white-space: nowrap;
      }

      @media (prefers-reduced-motion: reduce) {
        .arc-color-swatch *,
        .arc-color-swatch *::before,
        .arc-color-swatch *::after {
          animation-duration: 0.01ms !important;
          animation-iteration-count: 1 !important;
          transition-duration: 0.01ms !important;
        }
      }

/* arc-cta-banner */
.arc-cta-banner { display: block; position: relative; overflow: hidden; }

      .arc-cta-banner .cta {
        position: relative;
        padding: var(--space-3xl) var(--space-lg);
      }

      .arc-cta-banner .cta__bg {
        position: absolute;
        inset: 0;
        background:
          radial-gradient(ellipse at 30% 50%, rgba(var(--accent-primary-rgb), 0.1), transparent 60%),
          radial-gradient(ellipse at 70% 50%, rgba(var(--accent-secondary-rgb), 0.08), transparent 60%);
        pointer-events: none;
      }

      .arc-cta-banner[nogradient] .cta__bg { display: none; }

      .arc-cta-banner .cta__inner {
        position: relative;
        max-width: var(--max-width, 1200px);
        margin-inline: auto;
        display: flex;
        flex-direction: column;
        align-items: center;
        text-align: center;
        gap: var(--space-md);
      }

      .arc-cta-banner .cta__eyebrow {
        font-family: var(--font-accent);
        font-weight: 600;
        font-size: var(--text-xs);
        letter-spacing: 4px;
        text-transform: uppercase;
        background: var(--gradient-accent-text);
        -webkit-background-clip: text;
        -webkit-text-fill-color: transparent;
        background-clip: text;
      }

      .arc-cta-banner .cta__headline {
        font-size: clamp(28px, 4vw, 40px);
        font-weight: 500;
        letter-spacing: -1px;
        background: var(--gradient-display-text);
        -webkit-background-clip: text;
        -webkit-text-fill-color: transparent;
        background-clip: text;
        margin: 0;
      }

      .arc-cta-banner .cta__body {
        color: var(--text-secondary);
        font-size: var(--text-md);
        max-width: 480px;
        text-wrap: balance;
        line-height: 1.7;
      }

      .arc-cta-banner .cta__body ::slotted(*) { margin: 0; }

      .arc-cta-banner .cta__actions {
        display: flex;
        gap: var(--space-md);
        margin-top: var(--space-sm);
      }

      @media (max-width: 768px) { /* --breakpoint-md */
        .arc-cta-banner .cta { padding: var(--space-xl) var(--space-md); }
        .arc-cta-banner .cta__actions { flex-direction: column; align-items: center; }
      }

/* arc-divider */
.arc-divider { display: block; width: 100%; }

      .arc-divider .divider { width: 100%; height: 1px; }

      .arc-divider:not([data-variant]) .divider,
      .arc-divider[data-variant="subtle"] .divider { background: var(--gradient-divider); }

      .arc-divider[data-variant="glow"] .divider {
        position: relative;
        background: var(--gradient-divider-glow);
        box-shadow: 0 0 6px rgba(var(--accent-primary-rgb),0.08);
      }
      .arc-divider[data-variant="glow"] .divider::after {
        content: '';
        position: absolute;
        inset: 0;
        background: linear-gradient(90deg, transparent 0%, rgba(var(--accent-secondary-rgb),0.4) 50%, transparent 100%);
        background-size: 200% 100%;
        animation: divider-shimmer 6s ease-in-out infinite;
        mix-blend-mode: screen;
      }

      .arc-divider[data-variant="line-white"] .divider,
      .arc-divider[data-variant="line-primary"] .divider,
      .arc-divider[data-variant="line-gradient"] .divider {
        height: 2px;
        margin-inline: auto;
      }
      .arc-divider[data-variant="line-white"] .divider {
        max-width: 160px;
        background: linear-gradient(90deg, transparent, rgba(var(--text-primary-rgb),0.35), transparent);
      }
      .arc-divider[data-variant="line-primary"] .divider {
        max-width: 200px;
        background: linear-gradient(90deg, transparent, rgba(var(--accent-primary-rgb),0.7), transparent);
        box-shadow: 0 0 8px rgba(var(--accent-primary-rgb),0.3);
      }
      .arc-divider[data-variant="line-gradient"] .divider {
        max-width: 240px;
        background: var(--divider-glow);
        box-shadow: 0 0 10px rgba(var(--accent-primary-rgb),0.25);
      }

      /* Alignment — rewrite gradients to originate from one edge */
      .arc-divider[data-align="left"] .divider { margin-inline: 0; }
      .arc-divider[data-align="right"] .divider { margin-left: auto; margin-right: 0; }

      .arc-divider([align="left"]:not([variant])) .divider,
      .arc-divider([align="left"][variant="subtle"]) .divider {
        background: linear-gradient(90deg, var(--border-default), transparent);
      }
      .arc-divider([align="right"]:not([variant])) .divider,
      .arc-divider([align="right"][variant="subtle"]) .divider {
        background: linear-gradient(90deg, transparent, var(--border-default));
      }

      .arc-divider([align="left"][variant="glow"]) .divider {
        background: linear-gradient(90deg, rgba(var(--accent-primary-rgb),0.5), rgba(var(--accent-secondary-rgb),0.3), transparent);
      }
      .arc-divider([align="right"][variant="glow"]) .divider {
        background: linear-gradient(90deg, transparent, rgba(var(--accent-secondary-rgb),0.3), rgba(var(--accent-primary-rgb),0.5));
      }

      .arc-divider([align="left"][variant="line-white"]) .divider {
        background: linear-gradient(90deg, rgba(var(--text-primary-rgb),0.35), transparent);
      }
      .arc-divider([align="right"][variant="line-white"]) .divider {
        background: linear-gradient(90deg, transparent, rgba(var(--text-primary-rgb),0.35));
      }

      .arc-divider([align="left"][variant="line-primary"]) .divider {
        background: linear-gradient(90deg, rgba(var(--accent-primary-rgb),0.7), transparent);
      }
      .arc-divider([align="right"][variant="line-primary"]) .divider {
        background: linear-gradient(90deg, transparent, rgba(var(--accent-primary-rgb),0.7));
      }

      .arc-divider([align="left"][variant="line-gradient"]) .divider {
        background: linear-gradient(90deg, var(--accent-primary), var(--accent-secondary), transparent);
      }
      .arc-divider([align="right"][variant="line-gradient"]) .divider {
        background: linear-gradient(90deg, transparent, var(--accent-primary), var(--accent-secondary));
      }

      /* ── Vertical ── */
      .arc-divider[vertical] { display: inline-flex; width: auto; height: 100%; }
      .arc-divider[vertical] .divider { width: 1px; height: 100%; }

      .arc-divider([vertical]:not([variant])) .divider,
      .arc-divider([vertical][variant="subtle"]) .divider {
        background: linear-gradient(180deg, transparent, var(--border-default), transparent);
      }

      .arc-divider([vertical][variant="glow"]) .divider {
        background: linear-gradient(180deg, transparent, rgba(var(--accent-primary-rgb),0.5), rgba(var(--accent-secondary-rgb),0.3), transparent);
      }

      .arc-divider([vertical][variant="line-gradient"]) .divider {
        width: 2px;
        max-width: none;
        background: linear-gradient(180deg, transparent, var(--accent-primary), var(--accent-secondary), transparent);
        box-shadow: 0 0 10px rgba(var(--accent-primary-rgb),0.25);
      }

      .arc-divider([vertical][variant="line-primary"]) .divider {
        width: 2px;
        max-width: none;
        background: linear-gradient(180deg, transparent, rgba(var(--accent-primary-rgb),0.7), transparent);
        box-shadow: 0 0 8px rgba(var(--accent-primary-rgb),0.3);
      }

      .arc-divider([vertical][variant="line-white"]) .divider {
        width: 2px;
        max-width: none;
        background: linear-gradient(180deg, transparent, rgba(var(--text-primary-rgb),0.35), transparent);
      }

      /* Labeled divider */
      .arc-divider .divider--labeled {
        display: flex;
        align-items: center;
        gap: var(--space-md);
        height: auto;
        background: none !important;
        box-shadow: none !important;
      }

      .arc-divider .divider__line {
        flex: 1;
        height: 1px;
        background: var(--gradient-divider);
      }

      .arc-divider .divider__label {
        font-family: var(--font-accent);
        font-size: var(--text-xs);
        font-weight: 600;
        letter-spacing: 1.5px;
        text-transform: uppercase;
        color: var(--text-muted);
        white-space: nowrap;
        flex-shrink: 0;
      }

      @keyframes divider-shimmer {
        0%, 100% { background-position: 200% 0; }
        50% { background-position: -100% 0; }
      }

      @media (prefers-reduced-motion: reduce) {
        .arc-divider[data-variant="glow"] .divider::after { animation: none; }
      }

/* arc-empty-state */
.arc-empty-state { display: block; }

      .arc-empty-state .empty {
        display: flex;
        flex-direction: column;
        align-items: center;
        text-align: center;
        padding: var(--space-2xl) var(--space-xl);
        border: 1px dashed var(--border-default);
        border-radius: var(--radius-lg);
        background: var(--surface-raised);
      }

      .arc-empty-state .empty__icon {
        margin-bottom: var(--space-lg);
        color: var(--text-ghost);
        font-size: 40px; /* icon size, not text */
      }

      .arc-empty-state .empty__heading {
        margin: 0 0 var(--space-sm);
        font-family: var(--font-body);
        font-size: var(--heading-size);
        font-weight: var(--heading-weight);
        color: var(--text-primary);
      }

      .arc-empty-state .empty__desc {
        margin: 0 0 var(--space-lg);
        font-family: var(--font-body);
        font-size: var(--body-size);
        line-height: var(--body-lh);
        color: var(--text-muted);
        max-width: 360px;
      }

      .arc-empty-state .empty__actions {
        display: flex;
        gap: var(--space-sm);
      }

/* arc-feature-card */
.arc-feature-card { display: block; height: 100%; }

      .arc-feature-card .card { height: 100%; }

      .arc-feature-card .card__inner {
        padding: var(--space-lg);
        gap: var(--space-md);
        z-index: 1;
      }

      .arc-feature-card .card__icon {
        width: 44px;
        height: 44px;
        display: flex;
        align-items: center;
        justify-content: center;
        border-radius: var(--radius-md);
        background: var(--accent-primary-subtle);
        border: 1px solid var(--accent-primary-border);
        color: var(--accent-primary);
        font-size: 20px; /* icon size, not text */
        transition: box-shadow var(--transition-slow), border-color var(--transition-slow), transform var(--transition-slow);
      }

      .arc-feature-card .card:hover .card__icon {
        border-color: rgba(var(--accent-primary-rgb),0.3);
        box-shadow: 0 0 20px var(--accent-primary-glow), 0 0 6px var(--accent-primary-border);
        transform: translateY(-2px);
      }

      .arc-feature-card .card__title {
        font-size: 17px; /* heading size, keep hardcoded */
        font-weight: 600;
        color: var(--text-primary);
        transition: color var(--transition-slow);
        margin: 0;
      }

      .arc-feature-card .card:hover .card__title { color: var(--text-primary); }

      .arc-feature-card .card__desc {
        color: var(--text-secondary);
        font-family: var(--font-body);
        font-size: var(--text-sm);
        line-height: 1.7;
        flex: 1;
        margin: 0;
      }

      .arc-feature-card .card__action {
        display: inline-flex;
        align-items: center;
        gap: 6px;
        font-family: var(--font-accent);
        font-size: var(--text-xs);
        font-weight: 600;
        letter-spacing: 1.5px;
        text-transform: uppercase;
        color: var(--text-ghost);
        transition: color var(--transition-fast), gap var(--transition-fast);
      }

      .arc-feature-card .card:hover .card__action {
        color: var(--accent-primary);
        gap: 10px;
      }

      .arc-feature-card .card__action-arrow {
        display: inline-block;
        width: 14px;
        height: 14px;
        transition: transform var(--transition-fast);
      }

      .arc-feature-card .card:hover .card__action-arrow {
        transform: translateX(2px);
      }

      .arc-feature-card .card__rule {
        width: 32px;
        height: 1px;
        background: linear-gradient(90deg, var(--accent-primary), transparent);
        opacity: 0;
        transition: opacity var(--transition-slow), width var(--transition-slow);
      }

      .arc-feature-card .card:hover .card__rule { opacity: 0.5; width: 48px; }

      @media (max-width: 768px) { /* --breakpoint-md */
        .arc-feature-card .card__inner { padding: var(--space-md); }
      }

      @media (prefers-reduced-motion: reduce) {
        .arc-feature-card *,
        .arc-feature-card *::before,
        .arc-feature-card *::after {
          animation-duration: 0.01ms !important;
          animation-iteration-count: 1 !important;
          transition-duration: 0.01ms !important;
        }
      }

/* arc-icon */
.arc-icon {
        display: inline-flex;
        align-items: center;
        justify-content: center;
        color: currentColor;
        vertical-align: middle;
      }

      .arc-icon[data-size="xs"] { width: 12px; height: 12px; }
      .arc-icon:not([data-size]),
      .arc-icon[data-size="sm"] { width: 16px; height: 16px; }
      .arc-icon[data-size="md"] { width: 20px; height: 20px; }
      .arc-icon[data-size="lg"] { width: 24px; height: 24px; }
      .arc-icon[data-size="xl"] { width: 32px; height: 32px; }

      .arc-icon .icon {
        display: flex;
        align-items: center;
        justify-content: center;
        width: 100%;
        height: 100%;
      }

      svg {
        width: 100%;
        height: 100%;
      }

      ::slotted(svg) {
        width: 100%;
        height: 100%;
        fill: currentColor;
      }

/* arc-scroll-area */
.arc-scroll-area {
        display: block;
        position: relative;
      }

      .arc-scroll-area .scroll-area {
        overflow: hidden;
        scroll-behavior: smooth;
        border-radius: inherit;
      }

      /* Orientation variants */
      .arc-scroll-area[data-orientation="vertical"] .scroll-area,
      .arc-scroll-area:not([data-orientation]) .scroll-area {
        overflow-y: auto;
        overflow-x: hidden;
      }

      .arc-scroll-area[data-orientation="horizontal"] .scroll-area {
        overflow-x: auto;
        overflow-y: hidden;
      }

      .arc-scroll-area[data-orientation="both"] .scroll-area {
        overflow: auto;
      }

      /* Webkit scrollbar styling */
      .arc-scroll-area .scroll-area::-webkit-scrollbar {
        width: 6px;
        height: 6px;
      }

      .arc-scroll-area .scroll-area::-webkit-scrollbar-track {
        background: var(--surface-overlay);
        border-radius: var(--radius-full);
      }

      .arc-scroll-area .scroll-area::-webkit-scrollbar-thumb {
        background: var(--border-bright);
        border-radius: var(--radius-full);
        transition: background var(--transition-fast);
      }

      .arc-scroll-area .scroll-area::-webkit-scrollbar-thumb:hover {
        background: var(--text-ghost);
      }

      .arc-scroll-area .scroll-area::-webkit-scrollbar-corner {
        background: var(--surface-overlay);
      }

      /* Firefox scrollbar styling */
      .arc-scroll-area .scroll-area {
        scrollbar-width: thin;
        scrollbar-color: var(--border-bright) var(--surface-overlay);
      }

      @media (prefers-reduced-motion: reduce) {
        .arc-scroll-area *,
        .arc-scroll-area *::before,
        .arc-scroll-area *::after {
          animation-duration: 0.01ms !important;
          animation-iteration-count: 1 !important;
          transition-duration: 0.01ms !important;
        }
      }

/* arc-scroll-indicator */
.arc-scroll-indicator {
        display: block;
        position: sticky;
        top: 0;
        z-index: 100;
        pointer-events: none;
      }

      .arc-scroll-indicator[data-position="bottom"] {
        top: auto;
        bottom: 0;
      }

      .arc-scroll-indicator .bar {
        height: 2px;
        width: 100%;
        background: var(--surface-overlay);
        overflow: hidden;
      }

      .arc-scroll-indicator[data-size="sm"] .bar { height: 2px; }
      .arc-scroll-indicator[data-size="md"] .bar { height: 3px; }
      .arc-scroll-indicator[data-size="lg"] .bar { height: 4px; }

      .arc-scroll-indicator .bar__fill {
        height: 100%;
        background: var(--accent-primary);
        transform-origin: left;
        transition: transform 60ms linear;
        will-change: transform;
      }

      .arc-scroll-indicator[data-color="gradient"] .bar__fill {
        background: linear-gradient(90deg, var(--accent-primary), var(--accent-secondary));
      }

      @media (prefers-reduced-motion: reduce) {
        .arc-scroll-indicator .bar__fill { transition: none; }
      }

/* arc-separator */
.arc-separator {
        display: block;
        width: 100%;
      }

      .arc-separator[data-orientation="vertical"] {
        display: inline-flex;
        width: auto;
        height: 100%;
      }

      .arc-separator .separator {
        width: 100%;
        height: 1px;
        background: var(--border-default);
      }

      .arc-separator[data-variant="dashed"] .separator {
        background: none;
        border-top: 1px dashed var(--border-default);
        height: 0;
      }

      .arc-separator[data-variant="dotted"] .separator {
        background: none;
        border-top: 1px dotted var(--border-default);
        height: 0;
      }

      .arc-separator[data-variant="fade"] .separator {
        background: linear-gradient(90deg, transparent, var(--border-default), transparent);
      }

      /* Vertical */
      .arc-separator[data-orientation="vertical"] .separator {
        width: 1px;
        height: 100%;
        background: var(--border-default);
      }

      .arc-separator([orientation="vertical"][variant="dashed"]) .separator {
        background: none;
        border-top: none;
        border-left: 1px dashed var(--border-default);
        width: 0;
      }

      .arc-separator([orientation="vertical"][variant="dotted"]) .separator {
        background: none;
        border-top: none;
        border-left: 1px dotted var(--border-default);
        width: 0;
      }

      .arc-separator([orientation="vertical"][variant="fade"]) .separator {
        background: linear-gradient(180deg, transparent, var(--border-default), transparent);
      }

      /* Labeled */
      .arc-separator .separator--labeled {
        display: flex;
        align-items: center;
        gap: var(--space-md);
        height: auto;
        background: none;
        border: none;
      }

      .arc-separator .separator__line {
        flex: 1;
        height: 1px;
        background: var(--border-default);
      }

      .arc-separator[data-variant="dashed"] .separator__line {
        background: none;
        border-top: 1px dashed var(--border-default);
        height: 0;
      }

      .arc-separator[data-variant="dotted"] .separator__line {
        background: none;
        border-top: 1px dotted var(--border-default);
        height: 0;
      }

      .arc-separator[data-variant="fade"] .separator__line:first-child {
        background: linear-gradient(90deg, transparent, var(--border-default));
      }

      .arc-separator[data-variant="fade"] .separator__line:last-child {
        background: linear-gradient(90deg, var(--border-default), transparent);
      }

      .arc-separator .separator__label {
        font-family: var(--font-body);
        font-size: var(--text-sm);
        color: var(--text-muted);
        white-space: nowrap;
        flex-shrink: 0;
        user-select: none;
      }

/* arc-skeleton */
.arc-skeleton { display: block; }

      @keyframes shimmer {
        0%   { background-position: -200% 0; }
        100% { background-position: 200% 0; }
      }

      .arc-skeleton .skeleton {
        background: linear-gradient(
          90deg,
          var(--surface-overlay) 25%,
          rgba(var(--accent-primary-rgb), 0.04) 37%,
          var(--surface-overlay) 63%
        );
        background-size: 200% 100%;
        animation: shimmer 1.8s ease-in-out infinite;
      }

      .arc-skeleton[data-variant="text"] .skeleton {
        width: 100%;
        height: 1em;
        border-radius: var(--radius-sm);
      }

      .arc-skeleton[data-variant="circle"] .skeleton {
        border-radius: var(--radius-full);
      }

      .arc-skeleton[data-variant="rect"] .skeleton {
        border-radius: var(--radius-md);
      }

      .arc-skeleton .skeleton-group {
        display: flex;
        flex-direction: column;
        gap: var(--space-sm);
      }

      @media (prefers-reduced-motion: reduce) {
        .arc-skeleton *,
        .arc-skeleton *::before,
        .arc-skeleton *::after {
          animation-duration: 0.01ms !important;
          animation-iteration-count: 1 !important;
          transition-duration: 0.01ms !important;
        }
      }

/* arc-spinner */
.arc-spinner { display: inline-flex; }

      @keyframes spin {
        to { transform: rotate(360deg); }
      }

      .arc-spinner .spinner {
        border-radius: var(--radius-full);
        border-style: solid;
        border-color: var(--accent-primary);
        border-top-color: transparent;
        animation: spin 0.75s linear infinite;
        box-sizing: border-box;
      }

      .arc-spinner[data-size="sm"] .spinner { width: 16px; height: 16px; border-width: 2px; }
      .arc-spinner[data-size="md"] .spinner { width: 24px; height: 24px; border-width: 2.5px; }
      .arc-spinner[data-size="lg"] .spinner { width: 40px; height: 40px; border-width: 3px; }

      .arc-spinner[data-variant="primary"] .spinner {
        border-color: var(--accent-primary);
        border-top-color: transparent;
      }

      .arc-spinner[data-variant="secondary"] .spinner {
        border-color: var(--accent-secondary);
        border-top-color: transparent;
      }

      .arc-spinner[data-variant="white"] .spinner {
        border-color: var(--text-primary);
        border-top-color: transparent;
      }

      @media (prefers-reduced-motion: reduce) {
        .arc-spinner *,
        .arc-spinner *::before,
        .arc-spinner *::after {
          animation-duration: 0.01ms !important;
          animation-iteration-count: 1 !important;
          transition-duration: 0.01ms !important;
        }
      }

/* arc-stack */
.arc-stack {
        display: flex;
        flex-direction: column;
        gap: var(--space-md);
        align-items: stretch;
        justify-content: flex-start;
      }

      /* Direction */
      .arc-stack[data-direction="horizontal"] { flex-direction: row; }
      .arc-stack[data-direction="vertical"]   { flex-direction: column; }

      /* Gap */
      .arc-stack[data-gap="xs"]  { gap: var(--space-xs); }
      .arc-stack[data-gap="sm"]  { gap: var(--space-sm); }
      .arc-stack[data-gap="md"]  { gap: var(--space-md); }
      .arc-stack[data-gap="lg"]  { gap: var(--space-lg); }
      .arc-stack[data-gap="xl"]  { gap: var(--space-xl); }
      .arc-stack[data-gap="2xl"] { gap: var(--space-2xl); }

      /* Align */
      .arc-stack[data-align="start"]   { align-items: flex-start; }
      .arc-stack[data-align="center"]  { align-items: center; }
      .arc-stack[data-align="end"]     { align-items: flex-end; }
      .arc-stack[data-align="stretch"] { align-items: stretch; }

      /* Justify */
      .arc-stack[data-justify="start"]   { justify-content: flex-start; }
      .arc-stack[data-justify="center"]  { justify-content: center; }
      .arc-stack[data-justify="end"]     { justify-content: flex-end; }
      .arc-stack[data-justify="between"] { justify-content: space-between; }
      .arc-stack[data-justify="around"]  { justify-content: space-around; }

      /* Wrap */
      .arc-stack[wrap] { flex-wrap: wrap; }

/* arc-virtual-list */
.arc-virtual-list {
        display: block;
        overflow: auto;
        position: relative;
      }

      .arc-virtual-list .virtual-list__spacer {
        position: relative;
        width: 100%;
      }

      .arc-virtual-list .virtual-list__viewport {
        position: absolute;
        top: 0;
        left: 0;
        width: 100%;
      }

      ::slotted(*) {
        position: absolute;
        left: 0;
        width: 100%;
      }

/* arc-animated-number */
.arc-animated-number {
        display: inline-block;
        font-family: var(--font-mono);
        font-variant-numeric: tabular-nums;
      }

      .arc-animated-number .value {
        white-space: nowrap;
      }

/* arc-badge */
.arc-badge { display: inline-flex; }

      .arc-badge .badge {
        display: inline-flex;
        align-items: center;
        gap: var(--space-xs);
        font-family: var(--font-mono);
        font-weight: 500;
        font-size: var(--text-xs);
        letter-spacing: normal;
        text-transform: none;
        color: var(--text-muted);
        padding: var(--space-xs) var(--space-sm);
        border: 1px solid var(--border-default);
        border-radius: var(--radius-sm);
        background: var(--surface-hover);
        transition: box-shadow 200ms ease, border-color 200ms ease;
        line-height: 1.4;
      }

      .arc-badge[data-variant="primary"] .badge {
        border-color: var(--accent-primary-border);
        color: var(--accent-primary);
        background: rgba(var(--accent-primary-rgb), 0.06);
      }

      .arc-badge[data-variant="secondary"] .badge {
        border-color: var(--accent-secondary-border);
        color: var(--accent-secondary);
        background: rgba(var(--accent-secondary-rgb), 0.06);
      }

      .arc-badge[data-variant="success"] .badge {
        border-color: rgba(var(--color-success-rgb), 0.2);
        color: var(--color-success);
        background: rgba(var(--color-success-rgb), 0.06);
      }

      .arc-badge[data-variant="warning"] .badge {
        border-color: rgba(var(--color-warning-rgb), 0.2);
        color: var(--color-warning);
        background: rgba(var(--color-warning-rgb), 0.06);
      }

      .arc-badge[data-variant="error"] .badge {
        border-color: rgba(var(--color-error-rgb), 0.2);
        color: var(--color-error);
        background: rgba(var(--color-error-rgb), 0.06);
      }

      .arc-badge[data-variant="info"] .badge {
        border-color: rgba(var(--color-info-rgb), 0.2);
        color: var(--color-info);
        background: rgba(var(--color-info-rgb), 0.06);
      }

      .arc-badge:hover .badge { border-color: var(--border-bright); }
      .arc-badge[data-variant="primary"]:hover .badge { box-shadow: var(--interactive-hover); }
      .arc-badge[data-variant="secondary"]:hover .badge { box-shadow: 0 0 12px rgba(var(--accent-secondary-rgb), 0.15); }
      .arc-badge[data-variant="success"]:hover .badge { box-shadow: 0 0 12px rgba(var(--color-success-rgb), 0.15); }
      .arc-badge[data-variant="warning"]:hover .badge { box-shadow: 0 0 12px rgba(var(--color-warning-rgb), 0.15); }
      .arc-badge[data-variant="error"]:hover .badge { box-shadow: 0 0 12px rgba(var(--color-error-rgb), 0.15); }
      .arc-badge[data-variant="info"]:hover .badge { box-shadow: 0 0 12px rgba(var(--color-info-rgb), 0.15); }

      /* Sizes */
      .arc-badge[data-size="sm"] .badge { font-size: calc(var(--text-xs) - 1px); padding: 2px var(--space-xs); }
      .arc-badge[data-size="lg"] .badge { font-size: var(--text-sm); padding: var(--space-sm) var(--space-md); }

      @media (prefers-reduced-motion: reduce) {
        .arc-badge *,
        .arc-badge *::before,
        .arc-badge *::after {
          animation-duration: 0.01ms !important;
          animation-iteration-count: 1 !important;
          transition-duration: 0.01ms !important;
        }
      }

/* arc-comparison-column */


/* arc-comparison */
.arc-comparison {
        display: block;
      }

      .arc-comparison .comparison {
        border: 1px solid var(--border-subtle);
        border-radius: var(--radius-md);
        overflow: hidden;
      }

      .arc-comparison .grid {
        display: grid;
        width: 100%;
      }

      .arc-comparison .header-cell {
        font-family: var(--font-accent);
        font-weight: 600;
        font-size: var(--text-sm);
        letter-spacing: 1px;
        text-transform: uppercase;
        color: var(--text-primary);
        padding: var(--space-md);
        text-align: center;
        border-bottom: 1px solid var(--divider);
      }

      .arc-comparison .header-cell--feature {
        text-align: left;
      }

      .arc-comparison .header-cell--highlight {
        background: var(--accent-primary-subtle);
        color: var(--accent-primary);
      }

      .arc-comparison .row {
        display: contents;
      }

      .arc-comparison .row:hover > .cell {
        background: var(--surface-hover);
      }

      .arc-comparison .row:hover > .cell--highlight {
        background: rgba(var(--accent-primary-rgb), 0.06);
      }

      .arc-comparison .cell {
        padding: var(--space-sm) var(--space-md);
        text-align: center;
        font-family: var(--font-body);
        font-size: var(--text-sm);
        color: var(--text-secondary);
        border-bottom: 1px solid var(--divider);
        transition: background var(--transition-fast);
      }

      .arc-comparison .cell--feature {
        text-align: left;
        color: var(--text-secondary);
      }

      .arc-comparison .cell--highlight {
        background: rgba(var(--accent-primary-rgb), 0.03);
      }

      .arc-comparison .row:last-child > .cell {
        border-bottom: none;
      }

      .arc-comparison .check {
        color: var(--color-success);
        display: inline-flex;
        align-items: center;
        justify-content: center;
      }

      .arc-comparison .cross {
        color: var(--text-ghost);
        display: inline-flex;
        align-items: center;
        justify-content: center;
      }

      @media (prefers-reduced-motion: reduce) {
        .arc-comparison *,
        .arc-comparison *::before,
        .arc-comparison *::after {
          animation-duration: 0.01ms !important;
          animation-iteration-count: 1 !important;
          transition-duration: 0.01ms !important;
        }
      }

/* arc-description-item */
.arc-description-item {
        display: block;
      }

      .arc-description-item .item__term {
        font-family: var(--font-accent);
        font-weight: 600;
        font-size: var(--text-xs);
        letter-spacing: 2px;
        text-transform: uppercase;
        color: var(--text-muted);
        margin-bottom: var(--space-xs);
      }

      .arc-description-item .item__detail {
        font-family: var(--font-body);
        font-size: var(--text-sm);
        color: var(--text-primary);
        line-height: 1.6;
        margin: 0;
      }

      @media (prefers-reduced-motion: reduce) {
        .arc-description-item {
          transition: none;
        }
      }

/* arc-description-list */
.arc-description-list {
        display: block;
      }

      .arc-description-list .list {
        display: grid;
        grid-template-columns: repeat(var(--cols, 1), 1fr);
        gap: 0;
        margin: 0;
        padding: 0;
      }

      ::slotted(arc-description-item) {
        padding: var(--space-md) var(--space-sm);
      }

      @media (max-width: 640px) {
        .arc-description-list .list {
          grid-template-columns: 1fr !important;
        }
      }

      @media (prefers-reduced-motion: reduce) {
        .arc-description-list {
          transition: none;
        }
      }

/* arc-diff */
.arc-diff { display: block; }

      .arc-diff .diff {
        font-family: var(--font-mono);
        font-size: var(--code-size);
        line-height: var(--code-lh);
        background: var(--surface-primary);
        border: 1px solid var(--border-subtle);
        border-radius: var(--radius-md);
        overflow: hidden;
      }

      .arc-diff .diff__body {
        overflow-x: auto;
        scrollbar-width: thin;
        scrollbar-color: var(--border-default) transparent;
      }

      .arc-diff .diff__line {
        display: flex;
        padding: 1px var(--space-md);
      }

      .arc-diff .diff__line--added {
        background: rgba(var(--color-success-rgb), 0.08);
        color: var(--color-success);
      }

      .arc-diff .diff__line--removed {
        background: rgba(var(--color-error-rgb), 0.08);
        color: var(--color-error);
        text-decoration: line-through;
        opacity: 0.7;
      }

      .arc-diff .diff__line--unchanged {
        color: var(--text-secondary);
      }

      .arc-diff .diff__line-number {
        color: var(--text-ghost);
        user-select: none;
        padding-right: var(--space-sm);
        text-align: right;
        min-width: 3ch;
        flex-shrink: 0;
      }

      .arc-diff .diff__prefix {
        color: var(--text-ghost);
        width: 2ch;
        flex-shrink: 0;
        user-select: none;
      }

      .arc-diff .diff__content {
        white-space: pre;
        flex: 1;
        min-width: 0;
      }

      /* Side-by-side mode */
      .arc-diff[data-mode="side-by-side"] .diff__body {
        display: grid;
        grid-template-columns: 1fr 1fr;
      }

      .arc-diff[data-mode="side-by-side"] .diff__pane + .diff__pane {
        border-left: 1px solid var(--divider);
      }

      @media (prefers-reduced-motion: reduce) {
        .arc-diff {
          transition: none;
        }
      }

/* arc-key-value */
.arc-key-value {
        display: block;
      }

      .arc-key-value .kv-list {
        display: flex;
        flex-direction: column;
      }

      /* Horizontal layout — grid pairs */
      .arc-key-value[data-layout="horizontal"] ::slotted(arc-kv-pair) {
        display: grid;
        grid-template-columns: minmax(120px, auto) 1fr;
        gap: var(--space-md);
        align-items: baseline;
      }

      /* Stacked layout — flex column pairs */
      .arc-key-value[data-layout="stacked"] ::slotted(arc-kv-pair) {
        display: flex;
        flex-direction: column;
        gap: var(--space-xs);
      }

      /* Pair padding */
      ::slotted(arc-kv-pair) {
        padding: var(--space-md) var(--space-sm);
        border-radius: var(--radius-sm);
        transition: background var(--transition-fast);
      }

      ::slotted(arc-kv-pair:hover) {
        background: var(--surface-hover);
      }

      /* Dividers */
      .arc-key-value[dividers] ::slotted(arc-kv-pair:not(:last-child)) {
        border-bottom: 1px solid var(--divider);
      }

      @media (prefers-reduced-motion: reduce) {
        ::slotted(arc-kv-pair) {
          transition: none;
        }
      }

/* arc-kv-pair */
.arc-kv-pair {
        display: block;
      }

      .arc-kv-pair .kv__key {
        font-family: var(--font-accent);
        font-weight: 600;
        font-size: var(--text-xs);
        letter-spacing: 2px;
        text-transform: uppercase;
        color: var(--text-muted);
      }

      .arc-kv-pair .kv__value {
        font-family: var(--font-body);
        font-size: var(--text-sm);
        color: var(--text-primary);
      }

/* arc-meter */
.arc-meter { display: block; }

      .arc-meter .meter {
        display: flex;
        flex-direction: column;
        gap: var(--space-xs);
      }

      .arc-meter .meter__header {
        display: flex;
        align-items: center;
        justify-content: space-between;
      }

      .arc-meter .meter__label {
        font-family: var(--font-body);
        font-size: var(--body-size);
        color: var(--text-secondary);
        user-select: none;
      }

      .arc-meter .meter__value {
        font-family: var(--font-mono);
        font-size: var(--code-size);
        color: var(--text-muted);
      }

      .arc-meter .meter__track {
        position: relative;
        width: 100%;
        height: 8px;
        background: var(--surface-overlay);
        border-radius: var(--radius-full);
        overflow: hidden;
      }

      .arc-meter .meter__fill {
        height: 100%;
        border-radius: var(--radius-full);
        transition: width var(--transition-base), background var(--transition-base);
        min-width: 0;
      }

      .arc-meter .meter__fill--success { background: var(--color-success); }
      .arc-meter .meter__fill--warning { background: var(--color-warning); }
      .arc-meter .meter__fill--error   { background: var(--color-error); }

      @media (prefers-reduced-motion: reduce) {
        .arc-meter *,
        .arc-meter *::before,
        .arc-meter *::after {
          animation-duration: 0.01ms !important;
          animation-iteration-count: 1 !important;
          transition-duration: 0.01ms !important;
        }
      }

/* arc-sparkline */
.arc-sparkline {
        display: inline-block;
        vertical-align: middle;
      }

      svg {
        overflow: visible;
        display: block;
      }

      .arc-sparkline .sparkline-line {
        stroke: var(--_sparkline-color, var(--accent-primary));
        stroke-width: 1.5;
        stroke-linecap: round;
        stroke-linejoin: round;
        fill: none;
      }

      .arc-sparkline .sparkline-area {
        fill: rgba(var(--_sparkline-color-rgb, var(--accent-primary-rgb)), 0.1);
        stroke: none;
      }

      .arc-sparkline .sparkline-bar {
        fill: rgba(var(--_sparkline-color-rgb, var(--accent-primary-rgb)), 0.3);
        rx: 1;
        transition: fill var(--transition-fast, 150ms ease);
      }

      .arc-sparkline .sparkline-bar:hover {
        fill: rgba(var(--_sparkline-color-rgb, var(--accent-primary-rgb)), 0.6);
      }

      .arc-sparkline .sparkline-baseline {
        stroke: var(--border-subtle);
        stroke-width: 1;
      }

      /* Draw-in animation for line type */
      .arc-sparkline .sparkline-line-animated {
        animation: sparkline-draw 800ms ease-out forwards;
      }

      @keyframes sparkline-draw {
        from { stroke-dashoffset: var(--_dash-length); }
        to   { stroke-dashoffset: 0; }
      }

      .arc-sparkline .sparkline-area-animated {
        animation: sparkline-fade-in 800ms ease-out forwards;
        opacity: 0;
      }

      @keyframes sparkline-fade-in {
        from { opacity: 0; }
        to   { opacity: 1; }
      }

      @media (prefers-reduced-motion: reduce) {
        .arc-sparkline *,
        .arc-sparkline *::before,
        .arc-sparkline *::after {
          animation-duration: 0.01ms !important;
          animation-iteration-count: 1 !important;
          transition-duration: 0.01ms !important;
        }
      }

/* arc-stat */
.arc-stat { display: block; }

      .arc-stat .stat {
        display: flex;
        flex-direction: column;
        align-items: center;
        gap: var(--space-sm);
        text-align: center;
        padding: var(--space-lg);
      }

      .arc-stat .stat__value {
        font-size: clamp(32px, 4.5vw, 48px);
        font-weight: 200;
        letter-spacing: -1px;
        line-height: 1;
        background: var(--gradient-accent-text);
        -webkit-background-clip: text;
        -webkit-text-fill-color: transparent;
        background-clip: text;
        filter: drop-shadow(0 0 16px rgba(var(--accent-primary-rgb),0.3))
                drop-shadow(0 0 40px rgba(var(--accent-secondary-rgb),0.12));
      }

      .arc-stat .stat__rule {
        width: 24px;
        height: 1px;
        background: linear-gradient(90deg, transparent, var(--accent-primary), transparent);
        opacity: 0.4;
      }

      .arc-stat .stat__label {
        font-family: var(--font-accent);
        font-weight: 600;
        font-size: var(--label-inline-size);
        letter-spacing: var(--label-inline-spacing);
        text-transform: uppercase;
        color: var(--text-muted);
      }

      .arc-stat .stat__trend {
        display: inline-flex;
        align-items: center;
        gap: 4px;
        font-family: var(--font-mono);
        font-size: var(--text-sm);
        font-weight: 500;
        margin-top: var(--space-xs);
      }

      .arc-stat[data-trend="up"] .stat__trend { color: var(--color-success); }
      .arc-stat[data-trend="down"] .stat__trend { color: var(--color-error); }
      .arc-stat[data-trend="neutral"] .stat__trend { color: var(--text-muted); }

      .arc-stat .stat__trend-arrow {
        width: 12px;
        height: 12px;
      }

/* arc-stepper */
.arc-stepper { display: block; }

      .arc-stepper .stepper {
        display: flex;
        align-items: flex-start;
        gap: var(--space-xs);
      }

      .arc-stepper .step {
        display: flex;
        flex-direction: column;
        align-items: center;
        flex: 1;
        position: relative;
        padding: 0 var(--space-sm);
      }

      .arc-stepper .step__header {
        display: flex;
        align-items: center;
        width: 100%;
        position: relative;
      }

      .arc-stepper .step__circle {
        width: 36px;
        height: 36px;
        border-radius: var(--radius-full);
        display: flex;
        align-items: center;
        justify-content: center;
        font-family: var(--font-accent);
        font-size: var(--text-sm);
        font-weight: 700;
        letter-spacing: 1px;
        flex-shrink: 0;
        position: relative;
        z-index: 1;
        transition: background var(--transition-base),
                    color var(--transition-base),
                    border-color var(--transition-base),
                    box-shadow var(--transition-base);
        margin: 0 auto;
        box-sizing: border-box;
      }

      /* Upcoming (default) */
      .arc-stepper .step__circle {
        background: var(--surface-overlay);
        color: var(--text-ghost);
        border: 1px solid var(--border-default);
      }

      /* Active */
      .arc-stepper .step--active .step__circle {
        background: transparent;
        color: var(--accent-primary);
        border: 2px solid var(--accent-primary);
        box-shadow: 0 0 12px rgba(var(--accent-primary-rgb), 0.25);
        animation: pulse 2s ease-in-out infinite;
      }

      @keyframes pulse {
        0%, 100% {
          box-shadow: 0 0 12px rgba(var(--accent-primary-rgb), 0.25);
        }
        50% {
          box-shadow: 0 0 12px rgba(var(--accent-primary-rgb), 0.4);
        }
      }

      /* Completed */
      .arc-stepper .step--completed .step__circle {
        background: var(--accent-primary);
        color: var(--text-primary);
        border: 2px solid var(--accent-primary);
        box-shadow: 0 0 16px rgba(var(--accent-primary-rgb), 0.3);
      }

      .arc-stepper .step__line {
        position: absolute;
        top: 50%;
        height: 1px;
        background: var(--border-default);
        transform: translateY(-50%);
      }

      .arc-stepper .step__line--left {
        left: calc(-1 * var(--space-xs) - var(--space-sm));
        right: calc(50% + 20px);
      }

      .arc-stepper .step__line--right {
        left: calc(50% + 20px);
        right: calc(-1 * var(--space-xs) - var(--space-sm));
      }

      .arc-stepper .step--completed .step__line--left,
      .arc-stepper .step--active .step__line--left {
        background: var(--accent-primary);
      }

      .arc-stepper .step--completed .step__line--right {
        background: var(--accent-primary);
      }

      .arc-stepper .step__label {
        margin-top: var(--space-md);
        font-family: var(--font-accent);
        font-size: var(--text-xs);
        font-weight: 600;
        letter-spacing: 2px;
        text-transform: uppercase;
        color: var(--text-muted);
        text-align: center;
        transition: color var(--transition-base);
      }

      .arc-stepper .step--active .step__label {
        color: var(--text-primary);
      }

      .arc-stepper .step--completed .step__label {
        color: var(--text-secondary);
      }

      .arc-stepper .step__check {
        font-size: var(--text-sm);
        line-height: 1;
      }

      .arc-stepper .stepper__slot-host { display: none; }

      @media (prefers-reduced-motion: reduce) {
        .arc-stepper *,
        .arc-stepper *::before,
        .arc-stepper *::after {
          animation-duration: 0.01ms !important;
          animation-iteration-count: 1 !important;
          transition-duration: 0.01ms !important;
        }
        .arc-stepper .step--active .step__circle {
          animation: none !important;
        }
      }

/* arc-table */
.arc-table {
        display: block;
        font-family: var(--font-body);
        font-size: var(--body-size);
      }

      .arc-table .table-wrap {
        overflow-x: auto;
        border: 1px solid var(--border-subtle);
        border-radius: var(--radius-md);
      }

      table {
        width: 100%;
        border-collapse: collapse;
        font-size: var(--text-sm);
        color: var(--text-primary);
      }

      thead {
        background: var(--surface-overlay);
      }

      th {
        text-align: left;
        padding: var(--space-sm) var(--space-md);
        font-family: var(--font-accent);
        font-weight: 600;
        font-size: var(--text-xs);
        letter-spacing: 2px;
        text-transform: uppercase;
        color: var(--text-ghost);
        border-bottom: 1px solid var(--border-default);
        white-space: nowrap;
      }

      .arc-table[compact] th {
        padding: var(--space-xs) var(--space-sm);
      }

      td {
        padding: var(--space-sm) var(--space-md);
        border-bottom: 1px solid var(--divider);
        color: var(--text-secondary);
        line-height: 1.5;
        font-size: var(--text-sm);
      }

      .arc-table[compact] td {
        padding: var(--space-xs) var(--space-sm);
        font-size: var(--text-sm);
      }

      tr:last-child td {
        border-bottom: none;
      }

      .arc-table[striped] tbody tr:nth-child(odd) {
        background: var(--surface-primary);
      }

      .arc-table[striped] tbody tr:nth-child(even) {
        background: var(--surface-raised);
      }

      tbody tr {
        transition: background var(--transition-fast);
      }

      tbody tr:hover {
        background: var(--surface-hover);
      }

      @media (prefers-reduced-motion: reduce) {
        .arc-table *,
        .arc-table *::before,
        .arc-table *::after {
          animation-duration: 0.01ms !important;
          animation-iteration-count: 1 !important;
          transition-duration: 0.01ms !important;
        }
      }

/* arc-timeline */
.arc-timeline { display: block; }

      .arc-timeline .timeline {
        display: flex;
        flex-direction: column;
        gap: 0;
        padding: 0;
        margin: 0;
        list-style: none;
      }

      .arc-timeline .timeline__item {
        display: flex;
        gap: var(--space-lg);
        position: relative;
        padding-bottom: var(--space-xl);
      }

      .arc-timeline .timeline__item:last-child { padding-bottom: 0; }

      .arc-timeline .timeline__marker {
        display: flex;
        flex-direction: column;
        align-items: center;
        flex-shrink: 0;
        width: 24px;
        position: relative;
      }

      .arc-timeline .timeline__dot {
        width: 12px;
        height: 12px;
        border-radius: var(--radius-full);
        background: var(--accent-primary);
        border: 2px solid var(--surface-base);
        box-shadow:
          0 0 0 1px rgba(var(--accent-primary-rgb), 0.3),
          0 0 8px rgba(var(--accent-primary-rgb), 0.25);
        flex-shrink: 0;
        z-index: 1;
        position: relative;
        transition: box-shadow var(--transition-fast), transform var(--transition-fast);
      }

      .arc-timeline .timeline__item:hover .timeline__dot {
        box-shadow:
          0 0 0 2px rgba(var(--accent-primary-rgb), 0.4),
          0 0 14px rgba(var(--accent-primary-rgb), 0.4);
        transform: scale(1.2);
      }

      .arc-timeline .timeline__line {
        position: absolute;
        top: 12px;
        bottom: calc(-1 * var(--space-xl));
        left: 50%;
        width: 1px;
        transform: translateX(-50%);
        background: linear-gradient(180deg, rgba(var(--accent-primary-rgb), 0.4), var(--border-default) 40%);
      }

      .arc-timeline .timeline__item:last-child .timeline__line { display: none; }

      .arc-timeline .timeline__content {
        flex: 1;
        min-width: 0;
        padding-top: 0;
      }

      .arc-timeline .timeline__title {
        margin: 0;
        font-family: var(--font-accent);
        font-size: var(--text-xs);
        font-weight: 600;
        letter-spacing: 1.5px;
        text-transform: uppercase;
        color: var(--text-primary);
        line-height: 1.4;
        transition: color var(--transition-fast);
      }

      .arc-timeline .timeline__item:hover .timeline__title {
        color: var(--accent-primary);
      }

      .arc-timeline .timeline__desc {
        margin: var(--space-sm) 0 0;
        font-family: var(--font-body);
        font-size: var(--text-sm);
        line-height: 1.6;
        color: var(--text-muted);
      }

      .arc-timeline .timeline__date {
        margin: var(--space-sm) 0 0;
        font-family: var(--font-accent);
        font-size: var(--text-xs);
        font-weight: 600;
        letter-spacing: 2px;
        text-transform: uppercase;
        color: var(--text-ghost);
      }

      .arc-timeline .timeline__slot-host { display: none; }

      @media (prefers-reduced-motion: reduce) {
        .arc-timeline *,
        .arc-timeline *::before,
        .arc-timeline *::after {
          animation-duration: 0.01ms !important;
          animation-iteration-count: 1 !important;
          transition-duration: 0.01ms !important;
        }
      }

/* arc-value-card */
.arc-value-card { display: flex; flex-direction: column; height: 100%; }

      .arc-value-card .card {
        position: relative;
        display: flex;
        align-items: flex-start;
        gap: var(--space-lg);
        padding: var(--space-lg);
        flex: 1;
        border: 1px solid var(--border-subtle);
        border-radius: var(--radius-lg);
        transition: border-color var(--transition-base), box-shadow var(--transition-base);
      }

      .arc-value-card .card:hover {
        border-color: var(--border-bright);
        box-shadow: 0 0 20px rgba(var(--accent-secondary-rgb),0.06);
      }

      .arc-value-card .card__icon {
        flex-shrink: 0;
        color: var(--accent-secondary);
        font-size: 24px; /* icon size, not text */
        line-height: 1;
        padding-top: 2px;
      }

      .arc-value-card .card__text {
        display: flex;
        flex-direction: column;
        gap: var(--space-sm);
      }

      .arc-value-card .card__title {
        font-size: 17px; /* heading size, keep hardcoded */
        font-weight: 600;
        color: var(--text-primary);
        margin: 0;
      }

      .arc-value-card .card__desc {
        color: var(--text-secondary);
        font-family: var(--font-body);
        font-size: var(--text-sm);
        line-height: 1.7;
        margin: 0;
      }

      @media (prefers-reduced-motion: reduce) {
        .arc-value-card *,
        .arc-value-card *::before,
        .arc-value-card *::after {
          animation-duration: 0.01ms !important;
          animation-iteration-count: 1 !important;
          transition-duration: 0.01ms !important;
        }
      }

/* arc-blockquote */
.arc-blockquote {
        display: block;
      }

      .arc-blockquote .blockquote {
        position: relative;
        padding: var(--space-lg) var(--space-xl);
        margin: var(--space-lg) 0;
        background: rgba(var(--accent-primary-rgb), 0.02);
        border-radius: var(--radius-md);
      }

      /* Top gradient accent line */
      .arc-blockquote .blockquote::before {
        content: '';
        position: absolute;
        top: 0;
        left: var(--space-lg);
        right: var(--space-lg);
        height: 1px;
        background: linear-gradient(90deg, transparent, var(--accent-primary), var(--accent-secondary), transparent);
        opacity: 0.4;
      }

      /* Decorative opening quote mark */
      .arc-blockquote .blockquote::after {
        content: '\u201C';
        position: absolute;
        top: -8px;
        left: var(--space-md);
        font-size: 64px;
        font-weight: 200;
        line-height: 1;
        color: var(--text-ghost);
        opacity: 0.15;
        font-family: Georgia, serif;
        pointer-events: none;
      }

      .arc-blockquote .quote {
        font-family: var(--font-body);
        font-size: var(--text-lg);
        font-weight: 400;
        font-style: italic;
        color: var(--text-primary);
        line-height: 1.8;
      }

      .arc-blockquote([variant='accent']) .quote {
        background: var(--gradient-accent-text);
        -webkit-background-clip: text;
        -webkit-text-fill-color: transparent;
      }

      .arc-blockquote .cite {
        display: block;
        margin-top: var(--space-md);
        font-family: var(--font-accent);
        font-weight: 600;
        font-size: var(--text-xs);
        letter-spacing: 2px;
        text-transform: uppercase;
        color: var(--text-muted);
      }

      @media (prefers-reduced-motion: reduce) {
        *, *::before, *::after {
          animation-duration: 0s !important;
          transition-duration: 0s !important;
        }
      }

/* arc-code-block */
.arc-code-block { display: block; }

      .arc-code-block .code-block {
        position: relative;
        background: var(--surface-primary);
        border: 1px solid var(--border-default);
        border-radius: var(--radius-lg);
        overflow: hidden;
      }

      .arc-code-block .code-block__header {
        display: flex;
        align-items: center;
        justify-content: space-between;
        padding: var(--space-xs) var(--space-md);
        border-bottom: 1px solid var(--divider);
        background: var(--surface-raised);
      }

      .arc-code-block .code-block__filename {
        font-family: var(--font-mono);
        font-size: var(--text-sm);
        color: var(--text-muted);
      }

      .arc-code-block .code-block__lang {
        font-family: var(--font-mono);
        font-size: var(--text-xs);
        color: var(--text-ghost);
        text-transform: uppercase;
        letter-spacing: 1px;
      }

      .arc-code-block .code-block__body-wrap {
        position: relative;
      }

      .arc-code-block .code-block__body {
        padding: var(--space-md);
        padding-right: calc(var(--space-md) + 80px);
        overflow-x: auto;
        overflow-y: hidden;
      }

      /* Shiki CSS-variables theme — map --shiki-* to design tokens.
         Consumers override --accent-primary, --color-success, etc. and
         syntax colors follow automatically. */
      .arc-code-block .code-block {
        --shiki-foreground: var(--text-secondary);
        --shiki-background: var(--surface-primary);
        --shiki-token-comment: var(--text-ghost);
        --shiki-token-keyword: var(--accent-primary);
        --shiki-token-string: var(--color-success);
        --shiki-token-constant: var(--accent-secondary);
        --shiki-token-function: var(--text-primary);
        --shiki-token-parameter: var(--text-secondary);
        --shiki-token-string-expression: var(--color-success);
        --shiki-token-punctuation: var(--text-muted);
        --shiki-token-link: var(--accent-primary);
      }

      .arc-code-block .code-block__copy {
        position: absolute;
        top: var(--space-sm);
        right: var(--space-sm);
        z-index: 1;
        border-radius: var(--radius-sm);
        opacity: 0.75;
        backdrop-filter: blur(4px);
        transition: opacity var(--transition-fast);
      }

      .arc-code-block .code-block__copy:hover {
        opacity: 1;
      }

      .arc-code-block .code-block__body pre {
        margin: 0;
        background: transparent !important;
        font-family: var(--font-mono);
        font-size: var(--code-size);
        line-height: var(--code-lh);
        white-space: pre;
        tab-size: 2;
      }

      .arc-code-block .code-block__body pre code {
        font-family: inherit;
        font-size: inherit;
        line-height: inherit;
      }

      .arc-code-block .code-block__pre {
        margin: 0;
        font-family: var(--font-mono);
        font-size: var(--code-size);
        line-height: var(--code-lh);
        color: var(--text-primary);
        white-space: pre;
        tab-size: 2;
      }

      arc-status-bar {
        border-radius: 0;
      }

      arc-status-bar::part(base) {
        border-top-color: var(--divider);
      }

      /* — Window variant — */
      .arc-code-block[data-variant="window"] .code-block {
        box-shadow: 0 4px 24px rgba(0, 0, 0, 0.4);
      }

      .arc-code-block .code-block__titlebar {
        display: flex;
        align-items: center;
        padding: var(--space-sm) var(--space-md);
        border-bottom: 1px solid var(--divider);
        background: var(--surface-primary);
        position: relative;
      }

      .arc-code-block .code-block__orbs {
        display: flex;
        gap: 8px;
      }

      .arc-code-block .code-block__orb {
        width: 12px;
        height: 12px;
        border-radius: 50%;
      }

      .arc-code-block .code-block__orb--close    { background: #ff5f57; }
      .arc-code-block .code-block__orb--minimize { background: #febc2e; }
      .arc-code-block .code-block__orb--maximize { background: #28c840; }

      .arc-code-block .code-block__titlebar-filename {
        position: absolute;
        left: 50%;
        transform: translateX(-50%);
        font-family: var(--font-mono);
        font-size: var(--text-sm);
        color: var(--text-muted);
      }

      /* — Basic variant — */
      .arc-code-block[data-variant="basic"] .code-block__body-wrap {
        display: flex;
        align-items: center;
        padding: var(--space-xs) var(--space-sm) var(--space-xs) 0;
      }

      .arc-code-block[data-variant="basic"] .code-block__body {
        flex: 1;
        min-width: 0;
        padding: var(--space-sm);
        padding-right: var(--space-xs);
      }

      .arc-code-block[data-variant="basic"] .code-block__copy {
        position: static;
        flex-shrink: 0;
        order: 1;
        margin-left: var(--space-sm);
      }

      .arc-code-block .code-block__meta {
        font-family: var(--font-mono);
        font-size: var(--text-xs);
        color: var(--text-ghost);
      }

      @media (prefers-reduced-motion: reduce) {
        .arc-code-block *,
        .arc-code-block *::before,
        .arc-code-block *::after {
          animation-duration: 0.01ms !important;
          animation-iteration-count: 1 !important;
          transition-duration: 0.01ms !important;
        }
      }

/* arc-gradient-text */
.arc-gradient-text {
        display: inline;
      }

      .arc-gradient-text .gradient-text {
        -webkit-background-clip: text;
        -webkit-text-fill-color: transparent;
        background-clip: text;
        background-size: 100% 100%;
        filter: drop-shadow(0 0 12px rgba(var(--accent-primary-rgb), 0.2));
      }

      /* --- Variant gradients --- */

      .arc-gradient-text[data-variant="accent"] .gradient-text,
      .arc-gradient-text:not([data-variant]) .gradient-text {
        background: var(--gradient-accent-text);
        -webkit-background-clip: text;
        background-clip: text;
      }

      .arc-gradient-text[data-variant="display"] .gradient-text {
        background: var(--gradient-display-text);
        -webkit-background-clip: text;
        background-clip: text;
      }

      .arc-gradient-text[data-variant="sunset"] .gradient-text {
        background: linear-gradient(135deg, #ff6b6b, #ffa500, #ff4757);
        -webkit-background-clip: text;
        background-clip: text;
      }

      .arc-gradient-text[data-variant="ocean"] .gradient-text {
        background: linear-gradient(135deg, #00d2ff, #3a7bd5, #6dd5fa);
        -webkit-background-clip: text;
        background-clip: text;
      }

      /* custom variant handled via inline style in render() */

      /* --- Animation --- */

      .arc-gradient-text[animate] .gradient-text {
        background-size: 200% 200%;
        animation: gradient-shift 4s ease infinite;
      }

      @keyframes gradient-shift {
        0%   { background-position: 0% 50%; }
        50%  { background-position: 100% 50%; }
        100% { background-position: 0% 50%; }
      }

      @media (prefers-reduced-motion: reduce) {
        .arc-gradient-text[animate] .gradient-text {
          animation: none;
          background-size: 100% 100%;
        }
      }

/* arc-highlight */
.arc-highlight { display: inline; }

      mark {
        background: var(--accent-primary-subtle);
        color: var(--accent-primary);
        border-radius: var(--radius-sm);
        padding: 1px var(--space-xs); /* cosmetic 1px vertical for inline highlight */
        font-style: inherit;
        font-weight: inherit;
      }

/* arc-kbd */
.arc-kbd { display: inline; }

      .arc-kbd .kbd {
        display: inline-flex;
        align-items: center;
        font-family: var(--font-mono);
        font-size: var(--text-sm);
        line-height: 1;
        color: var(--text-secondary);
        background: var(--surface-overlay);
        border: 1px solid var(--border-default);
        border-bottom-width: 2px;
        border-radius: var(--radius-sm);
        padding: 2px calc(var(--space-xs) + 2px); /* cosmetic 2px vertical for kbd element */
        white-space: nowrap;
        user-select: none;
        vertical-align: baseline;
      }

/* arc-markdown */
.arc-markdown { display: block; }

      .arc-markdown .markdown {
        font-family: var(--font-body);
        font-size: var(--body-size);
        font-weight: var(--body-weight);
        line-height: var(--body-lh);
        color: var(--text-secondary);
      }

      .arc-markdown .markdown h1,
      .arc-markdown .markdown h2,
      .arc-markdown .markdown h3,
      .arc-markdown .markdown h4,
      .arc-markdown .markdown h5,
      .arc-markdown .markdown h6 {
        font-family: var(--font-body);
        color: var(--text-primary);
        line-height: 1.3;
        margin-top: var(--space-xl);
        margin-bottom: var(--space-md);
      }

      .arc-markdown .markdown h1 { font-size: var(--text-3xl); font-weight: 600; }
      .arc-markdown .markdown h2 { font-size: var(--heading-size); font-weight: 600; }
      .arc-markdown .markdown h3 { font-size: var(--text-lg); font-weight: 600; }
      .arc-markdown .markdown h4 { font-size: var(--body-size); font-weight: 600; }
      .arc-markdown .markdown h5 { font-size: var(--body-size); font-weight: 500; }
      .arc-markdown .markdown h6 { font-size: var(--code-size); font-weight: 500; text-transform: uppercase; letter-spacing: 1px; }

      .arc-markdown .markdown h1:first-child,
      .arc-markdown .markdown h2:first-child,
      .arc-markdown .markdown h3:first-child,
      .arc-markdown .markdown h4:first-child,
      .arc-markdown .markdown h5:first-child,
      .arc-markdown .markdown h6:first-child { margin-top: 0; }

      .arc-markdown .markdown p {
        margin: 0 0 var(--space-md) 0;
      }

      .arc-markdown .markdown p:last-child { margin-bottom: 0; }

      .arc-markdown .markdown strong { color: var(--text-primary); font-weight: 600; }

      .arc-markdown .markdown em { font-style: italic; }

      .arc-markdown .markdown a {
        color: var(--interactive);
        text-decoration: none;
        transition: color var(--transition-fast);
      }

      .arc-markdown .markdown a:hover {
        text-decoration: underline;
      }

      .arc-markdown .markdown code {
        font-family: var(--font-mono);
        font-size: var(--code-size);
        color: var(--accent-secondary);
        background: var(--surface-primary);
        padding: 2px calc(var(--space-xs) + 2px); /* cosmetic 2px vertical for inline code */
        border-radius: var(--radius-sm);
      }

      .arc-markdown .markdown pre {
        background: var(--surface-primary);
        border: 1px solid var(--border-subtle);
        border-radius: var(--radius-md);
        padding: var(--space-md);
        overflow-x: auto;
        margin: 0 0 var(--space-md) 0;
      }

      .arc-markdown .markdown pre code {
        background: none;
        padding: 0;
        border-radius: 0;
        font-size: var(--code-size);
        line-height: var(--code-lh);
        color: var(--text-primary);
      }

      .arc-markdown .markdown blockquote {
        margin: 0 0 var(--space-md) 0;
        padding: var(--space-sm);
        background: var(--surface-raised);
        border: 1px solid var(--border-subtle);
        border-radius: var(--radius-md);
      }

      .arc-markdown .markdown blockquote p:last-child { margin-bottom: 0; }

      .arc-markdown .markdown ul,
      .arc-markdown .markdown ol {
        margin: 0 0 var(--space-md) 0;
        padding-left: var(--space-lg);
        color: var(--text-secondary);
      }

      .arc-markdown .markdown li {
        margin-bottom: var(--space-xs);
      }

      .arc-markdown .markdown li:last-child { margin-bottom: 0; }

      .arc-markdown .markdown hr {
        border: none;
        height: 1px;
        background: var(--divider);
        margin: var(--space-xl) 0;
      }

      .arc-markdown .markdown img {
        max-width: 100%;
        height: auto;
        border-radius: var(--radius-md);
        margin: var(--space-sm) 0;
      }

      @media (prefers-reduced-motion: reduce) {
        .arc-markdown *,
        .arc-markdown *::before,
        .arc-markdown *::after {
          animation-duration: 0.01ms !important;
          animation-iteration-count: 1 !important;
          transition-duration: 0.01ms !important;
        }
      }

/* arc-number-format */
.arc-number-format {
        display: inline;
        font-family: var(--font-mono);
        font-variant-numeric: tabular-nums;
      }

/* arc-prose */
.arc-prose {
        display: block;
        color: var(--text-secondary);
        font-family: var(--font-body);
        line-height: var(--body-lh);
      }

      /* Size variants */
      .arc-prose[data-size="sm"] { font-size: var(--text-sm); }
      .arc-prose[data-size="md"], .arc-prose:not([data-size]) { font-size: var(--body-size); }
      .arc-prose[data-size="lg"] { font-size: var(--text-lg); }

      /* Direct-child block elements via ::slotted */
      ::slotted(h1) {
        font-size: var(--text-3xl) !important;
        font-weight: var(--heading-weight) !important;
        color: var(--text-primary) !important;
        margin-top: var(--space-2xl) !important;
        margin-bottom: var(--space-md) !important;
        line-height: 1.3 !important;
      }
      ::slotted(h2) {
        font-size: var(--heading-size) !important;
        font-weight: var(--heading-weight) !important;
        color: var(--text-primary) !important;
        margin-top: var(--space-xl) !important;
        margin-bottom: var(--space-md) !important;
        line-height: 1.4 !important;
      }
      ::slotted(h3) {
        font-size: var(--text-lg) !important;
        font-weight: 600 !important;
        color: var(--text-primary) !important;
        margin-top: var(--space-lg) !important;
        margin-bottom: var(--space-sm) !important;
      }
      ::slotted(h4) {
        font-size: var(--text-md) !important;
        font-weight: 600 !important;
        color: var(--text-primary) !important;
        margin-top: var(--space-lg) !important;
        margin-bottom: var(--space-sm) !important;
      }
      ::slotted(p) {
        margin-bottom: var(--space-md) !important;
        text-wrap: pretty !important;
      }
      ::slotted(ul),
      ::slotted(ol) {
        margin-bottom: var(--space-md) !important;
        padding-left: var(--space-lg) !important;
        color: var(--text-secondary) !important;
      }
      ::slotted(blockquote) {
        padding: var(--space-md) var(--space-lg) !important;
        margin: var(--space-lg) 0 !important;
        background: rgba(var(--accent-primary-rgb), 0.03) !important;
        border-radius: var(--radius-md) !important;
        font-style: italic !important;
        color: var(--text-muted) !important;
      }
      ::slotted(pre) {
        margin: var(--space-lg) 0 !important;
        padding: var(--space-md) !important;
        background: var(--surface-primary) !important;
        border: 1px solid var(--border-subtle) !important;
        border-radius: var(--radius-md) !important;
        overflow-x: auto !important;
        font-family: var(--font-mono) !important;
        font-size: var(--code-size) !important;
        line-height: var(--code-lh) !important;
      }
      ::slotted(hr) {
        border: none !important;
        height: 1px !important;
        background: var(--divider) !important;
        margin: var(--space-xl) 0 !important;
      }
      ::slotted(img) {
        max-width: 100% !important;
        height: auto !important;
        border-radius: var(--radius-md) !important;
        margin: var(--space-lg) 0 !important;
      }
      ::slotted(table) {
        width: 100% !important;
        border-collapse: collapse !important;
        margin: var(--space-lg) 0 !important;
        font-size: var(--text-sm) !important;
      }

      @media (prefers-reduced-motion: reduce) {
        .arc-prose * {
          transition: none !important;
        }
      }

/* arc-text */
.arc-text { display: block; }
      .arc-text[data-variant="accent"],
      .arc-text[data-variant="code"] { display: inline; }

      .arc-text .text--display {
        font-size: var(--display-xl-size);
        font-weight: var(--display-xl-weight);
        letter-spacing: var(--display-xl-spacing);
        line-height: 1.2;
        padding-bottom: 0.1em;
        background: var(--gradient-display-text);
        -webkit-background-clip: text;
        -webkit-text-fill-color: transparent;
        background-clip: text;
      }

      .arc-text .text--heading {
        font-size: var(--heading-size);
        font-weight: var(--heading-weight);
        color: var(--text-primary);
        line-height: 1.4;
        text-wrap: balance;
        margin-bottom: var(--space-md);
      }

      .arc-text .text--body {
        color: var(--text-secondary);
        font-family: var(--font-body);
        font-size: var(--body-size);
        font-weight: var(--body-weight);
        line-height: var(--body-lh);
        text-wrap: balance;
      }

      .arc-text .text--muted { color: var(--text-muted); }
      .arc-text .text--ghost { color: var(--text-ghost); }

      .arc-text .text--accent {
        font-family: var(--font-accent);
        font-weight: var(--ui-accent-weight);
        font-size: var(--ui-accent-size);
        letter-spacing: var(--ui-accent-spacing);
        background: var(--gradient-accent-text);
        -webkit-background-clip: text;
        -webkit-text-fill-color: transparent;
        background-clip: text;
        filter: drop-shadow(0 0 12px var(--accent-primary-glow));
      }

      .arc-text .text--label {
        font-family: var(--font-accent);
        font-weight: var(--section-title-weight);
        font-size: var(--section-title-size);
        letter-spacing: var(--section-title-spacing);
        text-transform: uppercase;
        color: var(--text-muted);
      }

      .arc-text .text--wordmark {
        font-weight: var(--wordmark-weight);
        font-size: var(--wordmark-size);
        letter-spacing: var(--wordmark-spacing);
        text-transform: uppercase;
        color: var(--text-primary);
        text-shadow: 0 0 30px var(--accent-primary-glow);
      }

      .arc-text .text--code {
        font-family: var(--font-mono);
        font-size: var(--code-size);
        line-height: var(--code-lh);
        color: var(--accent-secondary);
        text-shadow: 0 0 14px rgba(var(--accent-secondary-rgb),0.3);
      }

/* arc-time-ago */
.arc-time-ago {
        display: inline;
        font-family: var(--font-mono);
        font-size: inherit;
        color: inherit;
      }

      .arc-time-ago .time {
        cursor: default;
      }

/* arc-button-group */
.arc-button-group {
        display: inline-flex;
      }

      .arc-button-group .button-group {
        display: inline-flex;
        border-radius: var(--radius-md);
        overflow: hidden;
      }

      .arc-button-group[data-orientation="vertical"] .button-group {
        flex-direction: column;
      }

      /* Remove inner radii — connected borders */
      ::slotted(*) {
        --radius-md: 0;
        --radius-sm: 0;
        --radius-lg: 0;
        border-radius: 0 !important;
      }

      /* Horizontal: first/last get outer radii */
      .arc-button-group:not([data-orientation="vertical"]) ::slotted(:first-child) {
        border-radius: var(--_group-radius) 0 0 var(--_group-radius) !important;
      }

      .arc-button-group:not([data-orientation="vertical"]) ::slotted(:last-child) {
        border-radius: 0 var(--_group-radius) var(--_group-radius) 0 !important;
      }

      .arc-button-group:not([data-orientation="vertical"]) ::slotted(:only-child) {
        border-radius: var(--_group-radius) !important;
      }

      /* Vertical: first/last get outer radii */
      .arc-button-group[data-orientation="vertical"] ::slotted(:first-child) {
        border-radius: var(--_group-radius) var(--_group-radius) 0 0 !important;
      }

      .arc-button-group[data-orientation="vertical"] ::slotted(:last-child) {
        border-radius: 0 0 var(--_group-radius) var(--_group-radius) !important;
      }

      .arc-button-group[data-orientation="vertical"] ::slotted(:only-child) {
        border-radius: var(--_group-radius) !important;
      }

      /* Collapse borders between items */
      .arc-button-group:not([data-orientation="vertical"]) ::slotted(:not(:first-child)) {
        margin-left: -1px;
      }

      .arc-button-group[data-orientation="vertical"] ::slotted(:not(:first-child)) {
        margin-top: -1px;
      }

/* arc-button */
.arc-button { display: inline-flex; }
      .arc-button[disabled],
      .arc-button[loading] { pointer-events: none; }

      .arc-button[loading] .btn { opacity: 0.7; }

      .arc-button .btn__spinner {
        display: none;
        width: 14px;
        height: 14px;
        border: 2px solid currentColor;
        border-top-color: transparent;
        border-radius: var(--radius-full);
        animation: arc-btn-spin 600ms linear infinite;
      }

      .arc-button[loading] .btn__spinner { display: inline-block; }
      .arc-button[loading] .btn__label { opacity: 0.6; }

      @keyframes arc-btn-spin {
        to { transform: rotate(360deg); }
      }

      .arc-button .btn {
        display: inline-flex;
        align-items: center;
        justify-content: center;
        gap: var(--space-sm);
        font-family: var(--font-accent);
        font-weight: 600;
        text-transform: uppercase;
        letter-spacing: 2px;
        border: 1px solid transparent;
        border-radius: var(--radius-md);
        cursor: pointer;
        transition:
          background var(--transition-base),
          border-color var(--transition-base),
          box-shadow var(--transition-base),
          color var(--transition-base),
          transform 120ms var(--ease-out-expo);
        text-decoration: none;
        white-space: nowrap;
        box-sizing: border-box;
        min-height: var(--touch-min);
      }

      /* Sizes */
      .arc-button[data-size="sm"] .btn { font-size: var(--text-xs); padding: var(--space-xs) var(--space-md); }
      .arc-button:not([data-size]) .btn,
      .arc-button[data-size="md"] .btn { font-size: var(--text-xs); padding: var(--space-sm) var(--space-lg); }
      .arc-button[data-size="lg"] .btn { font-size: var(--text-xs); padding: var(--space-md) var(--space-xl); letter-spacing: 3px; }

      /* Default → primary */
      .arc-button:not([data-variant]) .btn {
        background: var(--interactive);
        color: var(--surface-base);
        border-color: var(--interactive);
      }
      .arc-button:not([data-variant]) .btn:hover { box-shadow: var(--interactive-active); }

      /* :active scale */
      .arc-button:not([data-variant]) .btn:active,
      .arc-button[data-variant="primary"] .btn:active { transform: scale(0.97); box-shadow: 0 0 8px rgba(var(--interactive-rgb),0.5); }
      .arc-button[data-variant="secondary"] .btn:active {
        transform: scale(0.97);
        background: rgba(var(--interactive-rgb),0.05);
      }
      .arc-button[data-variant="ghost"] .btn:active {
        transform: scale(0.97);
        background: var(--surface-overlay);
      }

      /* Prefix / Suffix */
      .arc-button .btn__prefix,
      .arc-button .btn__suffix {
        display: inline-flex;
        align-items: center;
      }

      .arc-button .btn__prefix--empty,
      .arc-button .btn__suffix--empty { display: none; }

      ::slotted([slot="prefix"]),
      ::slotted([slot="suffix"]) {
        display: flex;
      }

      @media (prefers-reduced-motion: reduce) {
        .arc-button *,
        .arc-button *::before,
        .arc-button *::after {
          animation-duration: 0.01ms !important;
          animation-iteration-count: 1 !important;
          transition-duration: 0.01ms !important;
        }
      }

/* arc-fieldset */
.arc-fieldset {
        display: block;
      }

      .arc-fieldset[disabled] {
        opacity: 0.5;
      }

      fieldset {
        border: 1px solid var(--border-default);
        border-radius: var(--radius-md);
        padding: var(--space-md) var(--space-lg) var(--space-lg);
        margin: 0;
        min-width: 0;
      }

      .arc-fieldset[data-variant="card"] fieldset {
        background: var(--surface-primary);
        box-shadow: var(--shadow-sm, 0 1px 2px rgba(0,0,0,0.05));
      }

      legend {
        font-family: var(--font-body);
        font-size: var(--body-size);
        font-weight: 600;
        color: var(--text-primary);
        padding: 0 var(--space-xs);
        display: flex;
        align-items: center;
        gap: var(--space-sm);
      }

      .arc-fieldset .legend__slot { display: contents; }
      .arc-fieldset .legend__slot--empty { display: none; }

      .arc-fieldset .fieldset__header {
        display: flex;
        align-items: center;
        justify-content: space-between;
        gap: var(--space-md);
      }

      .arc-fieldset .fieldset__actions {
        display: inline-flex;
        gap: var(--space-sm);
      }

      .arc-fieldset .fieldset__actions--empty { display: none; }

      .arc-fieldset .fieldset__description {
        font-family: var(--font-body);
        font-size: var(--text-sm);
        color: var(--text-muted);
        line-height: 1.5;
        margin-top: var(--space-xs);
        padding: 0 var(--space-xs);
      }

      .arc-fieldset .fieldset__content {
        display: flex;
        flex-direction: column;
        gap: var(--space-md);
        margin-top: var(--space-md);
      }

      .arc-fieldset .fieldset__error {
        font-family: var(--font-body);
        font-size: var(--text-sm);
        color: var(--status-error, #ef4444);
        margin-top: var(--space-sm);
        padding: 0 var(--space-xs);
      }

/* arc-icon-button */
.arc-icon-button { display: inline-flex; }
      .arc-icon-button[disabled] { pointer-events: none; }

      .arc-icon-button .btn {
        display: inline-flex;
        align-items: center;
        justify-content: center;
        gap: var(--space-xs);
        border: 1px solid transparent;
        border-radius: var(--radius-md);
        cursor: pointer;
        transition:
          background var(--transition-base),
          border-color var(--transition-base),
          box-shadow var(--transition-base),
          color var(--transition-base),
          transform 120ms var(--ease-out-expo);
        text-decoration: none;
        box-sizing: border-box;
        color: inherit;
      }

      /* Icon-only (square) */
      .arc-icon-button .btn:not(.btn--has-text) { aspect-ratio: 1; }

      /* With text */
      .arc-icon-button .btn--has-text {
        font-family: var(--font-accent);
        font-weight: 600;
        text-transform: uppercase;
        letter-spacing: 1.5px;
        white-space: nowrap;
      }

      .arc-icon-button .btn__text {
        line-height: 1;
      }

      /* Sizes — icon-only */
      .arc-icon-button .btn:not(.btn--has-text) { min-width: var(--touch-min); min-height: var(--touch-min); }
      .arc-icon-button[data-size="xs"] .btn:not(.btn--has-text) { width: 28px; height: 28px; border-radius: var(--radius-sm); }
      .arc-icon-button[data-size="sm"] .btn:not(.btn--has-text) { width: 32px; height: 32px; }
      .arc-icon-button:not([data-size]) .btn:not(.btn--has-text),
      .arc-icon-button[data-size="md"] .btn:not(.btn--has-text) { width: 36px; height: 36px; }
      .arc-icon-button[data-size="lg"] .btn:not(.btn--has-text) { width: 44px; height: 44px; }

      /* Sizes — with text */
      .arc-icon-button .btn--has-text { min-height: var(--touch-min); }
      .arc-icon-button[data-size="xs"] .btn--has-text { padding: var(--space-xs) var(--space-sm); font-size: var(--text-xs); }
      .arc-icon-button[data-size="sm"] .btn--has-text { padding: calc(var(--space-xs) + 2px) calc(var(--space-sm) + 2px); font-size: var(--text-xs); }
      .arc-icon-button:not([data-size]) .btn--has-text,
      .arc-icon-button[data-size="md"] .btn--has-text { padding: var(--space-xs) var(--space-sm); font-size: var(--text-xs); }
      .arc-icon-button[data-size="lg"] .btn--has-text { padding: var(--space-sm) var(--space-md); font-size: var(--text-xs); }

      /* Default → ghost */
      .arc-icon-button:not([data-variant]) .btn {
        background: transparent;
        color: var(--text-muted);
        border-color: transparent;
      }
      .arc-icon-button:not([data-variant]) .btn:hover {
        color: var(--text-primary);
        background: var(--surface-hover);
      }

      /* :active scale */
      .arc-icon-button:not([data-variant]) .btn:active,
      .arc-icon-button[data-variant="ghost"] .btn:active {
        transform: scale(0.93);
        background: var(--surface-overlay);
      }
      .arc-icon-button[data-variant="secondary"] .btn:active {
        transform: scale(0.93);
        background: rgba(var(--interactive-rgb), 0.05);
      }
      .arc-icon-button[data-variant="primary"] .btn:active {
        transform: scale(0.93);
        box-shadow: 0 0 8px rgba(var(--interactive-rgb), 0.5);
      }

      /* IconButton secondary uses text-secondary instead of text-primary */
      .arc-icon-button[data-variant="secondary"] .btn {
        color: var(--text-secondary);
      }

      /* IconButton secondary hover uses smaller glow */
      .arc-icon-button[data-variant="secondary"] .btn:hover {
        box-shadow: 0 0 16px var(--accent-primary-ring);
      }

      @media (prefers-reduced-motion: reduce) {
        .arc-icon-button *,
        .arc-icon-button *::before,
        .arc-icon-button *::after {
          animation-duration: 0.01ms !important;
          animation-iteration-count: 1 !important;
          transition-duration: 0.01ms !important;
        }
      }

/* arc-input-group */
.arc-input-group {
        display: flex;
      }

      .arc-input-group .input-group {
        display: flex;
        align-items: stretch;
        width: 100%;
        border-radius: var(--radius-md);
        overflow: hidden;
        border: 1px solid var(--border-default);
        transition: box-shadow var(--transition-fast), border-color var(--transition-fast);
        background: var(--surface-primary);
      }

      .arc-input-group .input-group:focus-within {
        border-color: var(--interactive);
        box-shadow: var(--interactive-focus);
      }

      .arc-input-group .input-group__addon {
        display: flex;
        align-items: center;
        padding: 0 var(--space-md);
        background: var(--surface-overlay);
        border-color: inherit;
        font-family: var(--font-body);
        font-size: var(--text-sm);
        color: var(--text-muted);
        white-space: nowrap;
        user-select: none;
      }

      .arc-input-group .input-group__addon--prefix {
        border-right: 1px solid var(--border-default);
      }

      .arc-input-group .input-group__addon--suffix {
        border-left: 1px solid var(--border-default);
      }

      .arc-input-group .input-group__addon--empty { display: none; }

      .arc-input-group .input-group__content {
        flex: 1;
        min-width: 0;
        display: flex;
      }

      /* Remove borders/radii from slotted inputs */
      ::slotted(arc-input),
      ::slotted(arc-select),
      ::slotted(input),
      ::slotted(select) {
        border: none !important;
        border-radius: 0 !important;
        box-shadow: none !important;
        flex: 1;
        min-width: 0;
      }

      /* Sizes */
      .arc-input-group[data-size="sm"] .input-group__addon { padding: 0 var(--space-sm); font-size: var(--text-xs); }
      .arc-input-group[data-size="lg"] .input-group__addon { padding: 0 var(--space-lg); font-size: var(--body-size); }

      @media (prefers-reduced-motion: reduce) {
        .arc-input-group .input-group { transition: none; }
      }

/* arc-switch-group */
.arc-switch-group {
        display: block;
      }

      .arc-switch-group[disabled] {
        opacity: 0.5;
        pointer-events: none;
      }

      fieldset {
        border: none;
        padding: 0;
        margin: 0;
        min-width: 0;
      }

      legend {
        font-family: var(--font-body);
        font-size: var(--text-sm);
        font-weight: 600;
        color: var(--text-secondary);
        padding: 0;
        margin-bottom: var(--space-sm);
      }

      .arc-switch-group .switch-group {
        display: flex;
        flex-direction: column;
        gap: var(--space-sm);
      }

      .arc-switch-group[data-orientation="horizontal"] .switch-group {
        flex-direction: row;
        flex-wrap: wrap;
        gap: var(--space-lg);
      }

/* arc-footer */
.arc-footer {
        display: block;
        background: var(--surface-base);
        color: var(--text-secondary);
        font-family: var(--font-body);
        font-size: var(--body-size);
      }

      .arc-footer[border] .footer {
        border-top: 1px solid var(--divider);
      }

      .arc-footer .footer {
        padding: var(--space-xl);
        padding-inline: var(--space-lg);
      }

      .arc-footer[contained] .footer {
        padding-inline: 0;
      }

      .arc-footer[compact] .footer {
        padding: var(--space-md);
      }

      .arc-footer .footer__brand {
        margin-bottom: var(--space-xl);
      }

      .arc-footer[compact] .footer__brand {
        margin-bottom: var(--space-md);
      }

      .arc-footer .footer__columns {
        display: grid;
        grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
        gap: var(--space-xl);
        margin-bottom: var(--space-xl);
      }

      .arc-footer[compact] .footer__columns {
        gap: var(--space-md);
        margin-bottom: var(--space-md);
      }

      .arc-footer .footer__social {
        display: flex;
        align-items: center;
        gap: var(--space-md);
        margin-bottom: var(--space-lg);
      }

      .arc-footer[compact] .footer__social {
        margin-bottom: var(--space-sm);
      }

      /* Center alignment */
      .arc-footer[data-align="center"] .footer { text-align: center; }
      .arc-footer[data-align="center"] .footer__columns { justify-items: center; }
      .arc-footer[data-align="center"] .footer__social { justify-content: center; }
      .arc-footer[data-align="center"] .footer__legal { text-align: center; }

      .arc-footer .footer__legal {
        position: relative;
        padding-top: var(--space-md);
        color: var(--text-muted);
        font-size: var(--text-sm);
      }

      .arc-footer .footer__legal::before {
        content: '';
        position: absolute;
        top: 0;
        left: 0;
        right: 0;
        height: 1px;
        background: var(--gradient-divider-glow);
      }

/* arc-link */
.arc-link { display: inline; }

      .arc-link .link {
        font-family: var(--font-body);
        font-size: inherit;
        color: var(--interactive);
        text-decoration: none;
        cursor: pointer;
        transition:
          color var(--transition-fast),
          opacity var(--transition-fast);
        border: none;
        background: none;
        padding: 0;
        min-height: var(--touch-min);
        display: inline-flex;
        align-items: center;
      }

      .arc-link .link:hover {
        text-decoration: underline;
        text-underline-offset: 3px;
      }

      /* Underline variants */
      .arc-link[data-underline="always"] .link {
        text-decoration: underline;
        text-underline-offset: 3px;
      }
      .arc-link[data-underline="never"] .link:hover {
        text-decoration: none;
      }

      .arc-link[data-variant="muted"] .link {
        color: var(--text-muted);
      }
      .arc-link[data-variant="muted"] .link:hover {
        color: var(--text-primary);
      }

      .arc-link[data-variant="nav"] .link {
        color: var(--text-secondary);
        font-size: var(--text-sm);
        display: inline-flex;
        align-items: center;
        gap: var(--space-xs);
      }
      .arc-link[data-variant="nav"] .link:hover {
        color: var(--text-primary);
        text-decoration: none;
      }

      .arc-link[active] .link {
        color: var(--interactive);
      }

      .arc-link .link:focus-visible {
        outline: none;
        box-shadow: var(--interactive-focus-ring);
        border-radius: var(--radius-xs);
      }

      .arc-link .link__external-icon {
        display: inline-block;
        width: 12px;
        height: 12px;
        margin-left: 2px; /* cosmetic micro-spacing for external icon */
        vertical-align: middle;
        opacity: 0.6;
      }

      @media (prefers-reduced-motion: reduce) {
        .arc-link *,
        .arc-link *::before,
        .arc-link *::after {
          animation-duration: 0.01ms !important;
          animation-iteration-count: 1 !important;
          transition-duration: 0.01ms !important;
        }
      }

/* arc-skip-link */
.arc-skip-link {
        display: contents;
      }

      .arc-skip-link .skip-link {
        position: fixed;
        top: var(--space-md);
        left: 50%;
        transform: translateX(-50%) translateY(-200%);
        z-index: var(--z-max);
        background: var(--interactive);
        color: white;
        padding: var(--space-xs) var(--space-lg);
        border-radius: var(--radius-full);
        font-family: var(--font-accent);
        font-size: var(--text-sm);
        font-weight: 600;
        text-decoration: none;
        transition: transform var(--transition-fast) var(--ease-out-expo);
        white-space: nowrap;
      }

      .arc-skip-link .skip-link:focus-visible {
        transform: translateX(-50%) translateY(0);
        box-shadow: var(--interactive-focus), 0 0 20px rgba(var(--interactive-rgb), 0.3);
        outline: none;
      }

/* arc-top-bar */
.arc-top-bar {
        display: block;
        width: 100%;
        z-index: 100;
      }

      .arc-top-bar[fixed] {
        position: fixed;
        top: 0;
        left: 0;
        right: 0;
      }

      .arc-top-bar .topbar {
        position: relative;
        height: var(--nav-height);
        background: color-mix(in srgb, var(--surface-base) 85%, transparent);
        backdrop-filter: blur(12px) saturate(130%);
        -webkit-backdrop-filter: blur(12px) saturate(130%);
        border-bottom: 1px solid var(--divider);
      }

      .arc-top-bar .topbar__content {
        display: flex;
        align-items: center;
        gap: var(--space-md);
        height: 100%;
        padding-inline: var(--space-lg);
      }

      arc-container { height: 100%; }
      arc-container::part(container) { height: 100%; }

      .arc-top-bar[contained] .topbar__content {
        padding-inline: 0;
      }

      .arc-top-bar .topbar__glow {
        position: absolute;
        bottom: -1px;
        left: 20%;
        right: 20%;
        height: 1px;
        background: linear-gradient(90deg, transparent, rgba(var(--accent-secondary-rgb), 0.2), rgba(var(--accent-primary-rgb), 0.15), transparent);
        opacity: 0;
        transition: opacity var(--transition-slow);
        pointer-events: none;
      }

      .arc-top-bar[scrolled] .topbar__glow {
        opacity: 1;
      }

      .arc-top-bar .topbar__brand {
        display: flex;
        align-items: center;
        gap: var(--space-sm);
        color: var(--text-primary);
        text-decoration: none;
        flex: 0 0 auto;
        overflow: visible;
      }

      .arc-top-bar .topbar__heading {
        font-family: var(--font-body);
        font-size: var(--wordmark-size);
        font-weight: var(--wordmark-weight);
        letter-spacing: var(--wordmark-spacing);
        text-transform: uppercase;
      }

      .arc-top-bar .topbar__center {
        flex: 1;
        display: flex;
        align-items: center;
        justify-content: center;
      }

      .arc-top-bar .topbar__actions {
        display: flex;
        align-items: center;
        gap: var(--space-sm);
        flex-shrink: 0;
      }

      .arc-top-bar .topbar__menu-btn {
        display: none;
        align-items: center;
        justify-content: center;
        width: 36px;
        height: 36px;
        min-width: 36px;
        aspect-ratio: 1;
        background: none;
        border: 1px solid var(--border-subtle);
        color: var(--text-primary);
        cursor: pointer;
        padding: 0;
        border-radius: var(--radius-sm);
        transition: background var(--transition-fast), border-color var(--transition-fast), box-shadow var(--transition-fast);
      }

      .arc-top-bar .topbar__menu-btn:hover {
        background: var(--surface-hover);
        border-color: var(--border-default);
      }

      .arc-top-bar .topbar__menu-btn:focus-visible {
        outline: none;
        box-shadow: var(--interactive-focus);
      }

      .arc-top-bar .topbar__menu-btn--open {
        border-color: rgba(var(--interactive-rgb), 0.3);
        background: rgba(var(--interactive-rgb), 0.06);
      }

      .arc-top-bar .topbar__hamburger {
        width: 16px;
        height: 12px;
        position: relative;
        display: flex;
        flex-direction: column;
        justify-content: space-between;
      }

      .arc-top-bar .topbar__hamburger-line {
        display: block;
        width: 100%;
        height: 1.5px;
        background: currentColor;
        border-radius: 1px; /* cosmetic rounding on 1.5px hamburger lines -- intentionally not tokenized */
        transition: transform 400ms var(--ease-out-expo), opacity 250ms ease, width 400ms var(--ease-out-expo);
        transform-origin: center;
      }

      .arc-top-bar .topbar__hamburger-line:nth-child(2) {
        width: 100%;
      }

      .arc-top-bar .topbar__menu-btn--open .topbar__hamburger-line:nth-child(1) {
        transform: translateY(5.25px) rotate(45deg);
      }

      .arc-top-bar .topbar__menu-btn--open .topbar__hamburger-line:nth-child(2) {
        opacity: 0;
        width: 0;
      }

      .arc-top-bar .topbar__menu-btn--open .topbar__hamburger-line:nth-child(3) {
        transform: translateY(-5.25px) rotate(-45deg);
      }

      @media (max-width: 900px) {
        .arc-top-bar .topbar__menu-btn { display: flex; }
      }

      @media (prefers-reduced-motion: reduce) {
        .arc-top-bar *,
        .arc-top-bar *::before,
        .arc-top-bar *::after {
          animation-duration: 0.01ms !important;
          animation-iteration-count: 1 !important;
          transition-duration: 0.01ms !important;
        }
      }

/* arc-aspect-grid */
.arc-aspect-grid {
        display: block;
      }

      .arc-aspect-grid .grid {
        display: grid;
        grid-template-columns: repeat(var(--_cols, 3), 1fr);
        gap: var(--space-md);
      }

      .arc-aspect-grid[data-gap="sm"] .grid {
        gap: var(--space-sm);
      }

      .arc-aspect-grid[data-gap="md"] .grid {
        gap: var(--space-md);
      }

      .arc-aspect-grid[data-gap="lg"] .grid {
        gap: var(--space-lg);
      }

      ::slotted(*) {
        aspect-ratio: var(--_ratio, 1 / 1);
        border: 1px solid var(--border-subtle);
        border-radius: var(--radius-md);
        overflow: hidden;
      }

/* arc-auth-shell */
.arc-auth-shell {
        display: block;
        box-sizing: border-box;
      }

      /* Centered variant */
      .arc-auth-shell .auth-shell--centered {
        display: flex;
        flex-direction: column;
        align-items: center;
        justify-content: center;
        min-height: 100vh;
        background: var(--surface-primary);
        padding: var(--space-xl) var(--space-lg);
        box-sizing: border-box;
      }

      .arc-auth-shell .auth-shell--centered .logo {
        margin-bottom: var(--space-xl);
        text-align: center;
      }

      .arc-auth-shell .auth-shell--centered .card {
        background: var(--surface-raised);
        border: 1px solid var(--border-default);
        border-radius: var(--radius-lg);
        padding: var(--space-xl);
        width: 100%;
        max-width: 420px;
        box-sizing: border-box;
      }

      .arc-auth-shell .auth-shell--centered .footer {
        margin-top: var(--space-lg);
        color: var(--text-muted);
        font-size: var(--text-sm);
        text-align: center;
      }

      /* Split variant */
      .arc-auth-shell .auth-shell--split {
        display: grid;
        grid-template-columns: 1fr 1fr;
        min-height: 100vh;
        box-sizing: border-box;
      }

      .arc-auth-shell .auth-shell--split .form-side {
        display: flex;
        flex-direction: column;
        align-items: center;
        justify-content: center;
        background: var(--surface-primary);
        padding: var(--space-xl) var(--space-lg);
      }

      .arc-auth-shell .auth-shell--split .logo {
        margin-bottom: var(--space-xl);
        text-align: center;
      }

      .arc-auth-shell .auth-shell--split .card {
        background: var(--surface-raised);
        border: 1px solid var(--border-default);
        border-radius: var(--radius-lg);
        padding: var(--space-xl);
        width: 100%;
        max-width: 420px;
        box-sizing: border-box;
      }

      .arc-auth-shell .auth-shell--split .footer {
        margin-top: var(--space-lg);
        color: var(--text-muted);
        font-size: var(--text-sm);
        text-align: center;
      }

      .arc-auth-shell .auth-shell--split .aside-side {
        display: flex;
        align-items: center;
        justify-content: center;
        background: var(--surface-base);
        padding: var(--space-xl);
      }

      @media (max-width: 768px) { /* --breakpoint-md */
        .arc-auth-shell .auth-shell--split {
          grid-template-columns: 1fr;
        }

        .arc-auth-shell .auth-shell--split .aside-side {
          display: none;
        }
      }

/* arc-center */
.arc-center {
        display: block;
        box-sizing: border-box;
        margin-inline: auto;
        max-width: var(--_max-width, 60ch);
        padding-inline: var(--space-lg);
      }

      .arc-center[intrinsic] {
        display: flex;
        flex-direction: column;
        align-items: center;
      }

      .arc-center[text] {
        text-align: center;
      }

/* arc-cluster */
.arc-cluster {
        display: flex;
        flex-wrap: wrap;
        gap: var(--space-sm);
        align-items: center;
      }

      /* Gap variants */
      .arc-cluster[data-gap="xs"] { gap: var(--space-xs); }
      .arc-cluster[data-gap="sm"] { gap: var(--space-sm); }
      .arc-cluster[data-gap="md"] { gap: var(--space-md); }
      .arc-cluster[data-gap="lg"] { gap: var(--space-lg); }
      .arc-cluster[data-gap="xl"] { gap: var(--space-xl); }

      /* Align variants */
      .arc-cluster[data-align="start"]  { align-items: flex-start; }
      .arc-cluster[data-align="center"] { align-items: center; }
      .arc-cluster[data-align="end"]    { align-items: flex-end; }

      /* Justify variants */
      .arc-cluster[data-justify="start"]         { justify-content: flex-start; }
      .arc-cluster[data-justify="center"]        { justify-content: center; }
      .arc-cluster[data-justify="end"]           { justify-content: flex-end; }
      .arc-cluster[data-justify="space-between"] { justify-content: space-between; }
      .arc-cluster[data-justify="space-around"]  { justify-content: space-around; }

/* arc-container */
.arc-container { display: block; }

      .arc-container .container {
        width: 100%;
        max-width: var(--max-width);
        margin-inline: auto;
        padding-inline: var(--space-lg);
      }

      .arc-container[narrow] .container,
      .arc-container[data-size="sm"] .container { max-width: var(--max-width-sm); }
      .arc-container[data-size="md"] .container { max-width: var(--max-width); }
      .arc-container[data-size="lg"] .container { max-width: 1400px; }
      .arc-container[data-size="xl"] .container { max-width: 1600px; }
      .arc-container[data-size="full"] .container { max-width: none; }

      /* Padding variants */
      .arc-container[data-padding="none"] .container { padding-inline: 0; }
      .arc-container[data-padding="sm"] .container { padding-inline: var(--space-sm); }
      .arc-container[data-padding="lg"] .container { padding-inline: var(--space-xl); }

/* arc-dashboard-grid */
.arc-dashboard-grid {
        display: block;
        box-sizing: border-box;
      }

      .arc-dashboard-grid .dashboard-grid {
        display: grid;
        grid-template-columns: repeat(
          auto-fill,
          minmax(min(var(--min-col, 280px), 100%), 1fr)
        );
        gap: var(--gap, var(--space-lg));
        padding: var(--space-lg);
      }

/* arc-dock */
.arc-dock {
        display: contents;
      }

      .arc-dock .dock {
        position: fixed;
        z-index: 100;
        background: var(--surface-primary);
        border: 1px solid var(--border-subtle);
        transition: transform var(--transition-base) var(--ease-out-expo);
        overflow-y: auto;
      }

      /* Bottom */
      .arc-dock[data-position="bottom"] .dock {
        bottom: 0;
        left: 0;
        right: 0;
        border-top: 1px solid var(--border-subtle);
        border-bottom: none;
      }

      .arc-dock([position="bottom"][auto-hide]:not([open]):not(:hover)) .dock {
        transform: translateY(100%);
      }

      /* Left */
      .arc-dock[data-position="left"] .dock {
        top: 0;
        bottom: 0;
        left: 0;
        border-right: 1px solid var(--border-subtle);
        border-left: none;
      }

      .arc-dock([position="left"][auto-hide]:not([open]):not(:hover)) .dock {
        transform: translateX(-100%);
      }

      /* Right */
      .arc-dock[data-position="right"] .dock {
        top: 0;
        bottom: 0;
        right: 0;
        border-left: 1px solid var(--border-subtle);
        border-right: none;
      }

      .arc-dock([position="right"][auto-hide]:not([open]):not(:hover)) .dock {
        transform: translateX(100%);
      }

      /* Subtle glow on reveal */
      .arc-dock[auto-hide] .dock:hover,
      .arc-dock([auto-hide][open]) .dock {
        box-shadow: 0 0 20px rgba(var(--accent-primary-rgb), 0.08);
      }

/* arc-float-bar */
.arc-float-bar {
        display: contents;
      }

      .arc-float-bar .float-bar {
        position: fixed;
        left: 50%;
        transform: translateX(-50%) translateY(0);
        background: var(--surface-overlay);
        backdrop-filter: blur(12px);
        border: 1px solid var(--border-default);
        border-radius: var(--radius-lg);
        box-shadow: var(--shadow-overlay);
        padding: var(--space-sm);
        display: flex;
        align-items: center;
        gap: var(--space-sm);
        z-index: 100;
        transition: transform var(--transition-base) var(--ease-out-expo),
                    opacity var(--transition-base) var(--ease-out-expo);
        opacity: 1;
      }

      /* Bottom (default) */
      .arc-float-bar:not([data-position="top"]) .float-bar {
        bottom: var(--space-lg);
      }

      .arc-float-bar(:not([position="top"]):not([open])) .float-bar {
        transform: translateX(-50%) translateY(calc(100% + var(--space-lg)));
        opacity: 0;
        pointer-events: none;
      }

      /* Top */
      .arc-float-bar[data-position="top"] .float-bar {
        top: var(--space-lg);
      }

      .arc-float-bar([position="top"]:not([open])) .float-bar {
        transform: translateX(-50%) translateY(calc(-100% - var(--space-lg)));
        opacity: 0;
        pointer-events: none;
      }

/* arc-inset */
.arc-inset {
        display: block;
        padding: var(--space-md);
      }

      .arc-inset[data-space="xs"] { padding: var(--space-xs); }
      .arc-inset[data-space="sm"] { padding: var(--space-sm); }
      .arc-inset[data-space="md"] { padding: var(--space-md); }
      .arc-inset[data-space="lg"] { padding: var(--space-lg); }
      .arc-inset[data-space="xl"] { padding: var(--space-xl); }
      .arc-inset[data-space="2xl"] { padding: var(--space-2xl); }

      .arc-inset[bleed] { margin: calc(-1 * var(--_pad)); }
      .arc-inset([bleed][space="xs"]) { --_pad: var(--space-xs); }
      .arc-inset([bleed][space="sm"]) { --_pad: var(--space-sm); }
      .arc-inset([bleed]:not([space])),
      .arc-inset([bleed][space="md"]) { --_pad: var(--space-md); }
      .arc-inset([bleed][space="lg"]) { --_pad: var(--space-lg); }
      .arc-inset([bleed][space="xl"]) { --_pad: var(--space-xl); }
      .arc-inset([bleed][space="2xl"]) { --_pad: var(--space-2xl); }

/* arc-masonry */
.arc-masonry {
        display: block;
      }

      .arc-masonry .masonry {
        column-count: var(--_cols, 3);
        column-gap: var(--space-md);
      }

      .arc-masonry[data-gap="sm"] .masonry {
        column-gap: var(--space-sm);
      }

      .arc-masonry[data-gap="md"] .masonry {
        column-gap: var(--space-md);
      }

      .arc-masonry[data-gap="lg"] .masonry {
        column-gap: var(--space-lg);
      }

      ::slotted(*) {
        break-inside: avoid;
        margin-bottom: var(--space-md);
      }

      .arc-masonry[data-gap="sm"] ::slotted(*) {
        margin-bottom: var(--space-sm);
      }

      .arc-masonry[data-gap="lg"] ::slotted(*) {
        margin-bottom: var(--space-lg);
      }

/* arc-page-header */
.arc-page-header {
        display: block;
        font-family: var(--font-body);
      }

      .arc-page-header .page-header {
        padding: 0 0 var(--space-md);
      }

      .arc-page-header[border] .page-header {
        border-bottom: 1px solid var(--divider);
      }

      .arc-page-header .page-header__above {
        margin-bottom: var(--space-sm);
      }

      .arc-page-header .page-header__title-row {
        display: flex;
        align-items: center;
        justify-content: space-between;
        gap: var(--space-md);
        flex-wrap: wrap;
      }

      .arc-page-header .page-header__heading {
        margin: 0;
        font-family: var(--font-body);
        font-size: 28px;
        font-weight: 700;
        color: var(--text-primary);
        line-height: 1.2;
      }

      .arc-page-header .page-header__aside {
        display: flex;
        align-items: center;
        gap: var(--space-sm);
        flex-shrink: 0;
      }

      .arc-page-header .page-header__description {
        margin-top: var(--space-sm);
        color: var(--text-secondary);
        font-size: var(--body-size);
        line-height: 1.5;
      }

      .arc-page-header .page-header__below {
        margin-top: var(--space-md);
      }

      .arc-page-header .page-header__content {
        margin-top: var(--space-md);
      }

/* arc-page-layout */
.arc-page-layout {
        display: block;
        box-sizing: border-box;
      }

      .arc-page-layout .page-layout {
        padding: var(--space-xl) var(--space-lg);
        gap: var(--gap);
        min-height: 100%;
        box-sizing: border-box;
      }

      /* Centered layout */
      .arc-page-layout([layout='centered']) .page-layout {
        display: block;
        max-width: var(--max-width);
        margin: 0 auto;
      }

      /* Wide layout */
      .arc-page-layout([layout='wide']) .page-layout {
        display: block;
      }

      /* Sidebar left layout */
      .arc-page-layout([layout='sidebar-left']) .page-layout {
        display: grid;
        grid-template-columns: 240px 1fr;
      }

      /* Sidebar right layout */
      .arc-page-layout([layout='sidebar-right']) .page-layout {
        display: grid;
        grid-template-columns: 1fr 300px;
      }

      .arc-page-layout .sidebar {
        display: none;
      }

      .arc-page-layout([layout='sidebar-left']) .sidebar {
        display: block;
      }

      .arc-page-layout .aside {
        display: none;
      }

      .arc-page-layout([layout='sidebar-right']) .aside {
        display: block;
      }

      .arc-page-layout .main {
        min-width: 0;
      }

      @media (max-width: 768px) { /* --breakpoint-md */
        .arc-page-layout([layout='sidebar-left']) .page-layout,
        .arc-page-layout([layout='sidebar-right']) .page-layout {
          grid-template-columns: 1fr;
        }
      }

/* arc-responsive-switcher */
.arc-responsive-switcher {
        display: block;
        container-type: inline-size;
      }

      .arc-responsive-switcher .switcher {
        display: flex;
        flex-direction: column;
        gap: var(--space-md);
      }

      .arc-responsive-switcher[data-gap="xs"] .switcher { gap: var(--space-xs); }
      .arc-responsive-switcher[data-gap="sm"] .switcher { gap: var(--space-sm); }
      .arc-responsive-switcher[data-gap="md"] .switcher { gap: var(--space-md); }
      .arc-responsive-switcher[data-gap="lg"] .switcher { gap: var(--space-lg); }
      .arc-responsive-switcher[data-gap="xl"] .switcher { gap: var(--space-xl); }

      @container (min-width: 600px) {
        .arc-responsive-switcher .switcher {
          flex-direction: row;
        }
      }

      ::slotted(*) {
        flex: 1;
      }

/* arc-section */
.arc-section { display: block; }

      .arc-section .section {
        width: 100%;
        max-width: var(--max-width);
        margin-inline: auto;
        padding: var(--space-3xl) var(--space-lg);
        scroll-margin-top: var(--space-md);
      }

      @media (max-width: 768px) { /* --breakpoint-md */
        .arc-section .section { padding: var(--space-2xl) var(--space-md); }
      }

      .arc-section .section__label {
        display: block;
        font-family: var(--font-accent);
        font-weight: var(--section-title-weight);
        font-size: var(--section-title-size);
        letter-spacing: var(--section-title-spacing);
        text-transform: uppercase;
        color: var(--text-muted);
        margin-bottom: var(--space-lg);
      }

/* arc-settings-layout */
.arc-settings-layout {
        display: block;
        box-sizing: border-box;
      }

      /* Left nav layout */
      .arc-settings-layout .settings-layout--left {
        display: grid;
        grid-template-columns: 220px 1fr;
        min-height: 100%;
      }

      .arc-settings-layout .settings-layout--left .nav {
        padding: var(--space-lg);
        background: var(--surface-raised);
        border-right: 1px solid var(--divider);
      }

      .arc-settings-layout .settings-layout--left .content {
        padding: var(--space-xl);
        flex: 1;
      }

      /* Top nav layout */
      .arc-settings-layout .settings-layout--top {
        display: flex;
        flex-direction: column;
        min-height: 100%;
      }

      .arc-settings-layout .settings-layout--top .nav {
        padding: var(--space-lg);
        background: var(--surface-raised);
        border-bottom: 1px solid var(--divider);
      }

      .arc-settings-layout .settings-layout--top .content {
        padding: var(--space-xl);
        flex: 1;
      }

      @media (max-width: 768px) { /* --breakpoint-md */
        .arc-settings-layout .settings-layout--left {
          display: flex;
          flex-direction: column;
        }

        .arc-settings-layout .settings-layout--left .nav {
          border-right: none;
          border-bottom: 1px solid var(--divider);
        }
      }

/* arc-status-bar */
.arc-status-bar {
        display: block;
        font-family: var(--font-mono);
        font-size: var(--text-sm);
        color: var(--text-muted);
      }

      .arc-status-bar([position='fixed']) {
        position: fixed;
        bottom: 0;
        left: 0;
        right: 0;
        z-index: 100;
      }

      .arc-status-bar .status-bar {
        display: flex;
        align-items: center;
        height: 28px;
        padding: 0 var(--space-sm);
        background: var(--surface-base);
        border-top: 1px solid var(--divider);
        gap: var(--space-sm);
      }

      .arc-status-bar .status-bar__start {
        display: flex;
        align-items: center;
        gap: var(--space-sm);
        flex-shrink: 0;
      }

      .arc-status-bar .status-bar__center {
        display: flex;
        align-items: center;
        gap: var(--space-sm);
        flex: 1;
        justify-content: center;
      }

      .arc-status-bar .status-bar__end {
        display: flex;
        align-items: center;
        gap: var(--space-sm);
        flex-shrink: 0;
        margin-left: auto;
      }

/* arc-toolbar */
.arc-toolbar {
        display: block;
        font-family: var(--font-body);
      }

      .arc-toolbar[sticky] {
        position: sticky;
        top: 0;
        z-index: 50;
      }

      .arc-toolbar .toolbar {
        display: flex;
        align-items: center;
        height: 48px;
        padding: 0 var(--space-md);
        background: var(--surface-raised);
        gap: var(--space-sm);
      }

      .arc-toolbar([size='sm']) .toolbar {
        height: 36px;
        padding: 0 var(--space-sm);
      }

      .arc-toolbar[border] .toolbar {
        border-bottom: 1px solid var(--divider);
      }

      .arc-toolbar .toolbar__start {
        display: flex;
        align-items: center;
        gap: var(--space-sm);
        flex-shrink: 0;
      }

      .arc-toolbar .toolbar__center {
        display: flex;
        align-items: center;
        gap: var(--space-sm);
        flex: 1;
        justify-content: center;
      }

      .arc-toolbar .toolbar__end {
        display: flex;
        align-items: center;
        gap: var(--space-sm);
        flex-shrink: 0;
        margin-left: auto;
      }

/* arc-announcement */
.arc-announcement {
        position: absolute;
        width: 1px;
        height: 1px;
        overflow: hidden;
        clip: rect(0,0,0,0);
        clip-path: inset(50%);
        white-space: nowrap;
      }

/* arc-inline-message */
.arc-inline-message {
        display: flex;
        align-items: flex-start;
        gap: var(--space-xs);
      }

      .arc-inline-message .inline-message__icon {
        color: var(--_status-color);
        flex-shrink: 0;
        font-size: var(--text-sm);
        line-height: 1.6;
      }

      .arc-inline-message .inline-message__content {
        font-family: var(--font-body);
        font-size: var(--text-sm);
        color: var(--text-muted);
        line-height: 1.6;
      }

/* arc-loading-overlay */
.arc-loading-overlay { display: contents; }

      .arc-loading-overlay .loading-overlay {
        position: absolute;
        inset: 0;
        z-index: 50;
        display: flex;
        flex-direction: column;
        align-items: center;
        justify-content: center;
        gap: var(--space-md);
        background: rgba(var(--bg-surface-rgb, 0,0,0), 0.6);
        backdrop-filter: blur(4px);
        opacity: 0;
        visibility: hidden;
        transition: opacity var(--transition-base), visibility var(--transition-base);
      }

      .arc-loading-overlay[active] .loading-overlay {
        opacity: 1;
        visibility: visible;
      }

      .arc-loading-overlay[global] .loading-overlay {
        position: fixed;
        z-index: var(--z-overlay);
      }

      .arc-loading-overlay .loading-overlay__spinner {
        width: 32px;
        height: 32px;
        border: 3px solid var(--border-subtle);
        border-top-color: var(--accent-primary);
        border-radius: 50%;
        animation: lo-spin 0.8s linear infinite;
      }

      .arc-loading-overlay .loading-overlay__message {
        font-family: var(--font-body);
        font-size: var(--text-sm);
        color: var(--text-muted);
      }

      @keyframes lo-spin {
        to { transform: rotate(360deg); }
      }

      @media (prefers-reduced-motion: reduce) {
        .arc-loading-overlay .loading-overlay__spinner { animation-duration: 1.5s; }
        .arc-loading-overlay .loading-overlay { transition: none; }
      }

/* arc-progress */
.arc-progress { display: block; }

      .arc-progress .progress__label {
        font-family: var(--font-accent);
        font-weight: 600;
        font-size: var(--label-inline-size);
        letter-spacing: var(--label-inline-spacing);
        text-transform: uppercase;
        color: var(--text-muted);
        margin-bottom: var(--space-xs);
        display: block;
      }

      /* Bar */
      .arc-progress .progress__track {
        width: 100%;
        border-radius: var(--radius-full);
        background: var(--border-subtle);
        overflow: hidden;
      }

      .arc-progress[data-size="sm"] .progress__track { height: 4px; }
      .arc-progress:not([data-size]) .progress__track,
      .arc-progress[data-size="md"] .progress__track { height: 8px; }
      .arc-progress[data-size="lg"] .progress__track { height: 12px; }

      .arc-progress .progress__fill {
        height: 100%;
        border-radius: var(--radius-full);
        background: var(--gradient-accent-text);
        transition: width var(--transition-base);
        box-shadow: 0 0 8px rgba(var(--accent-primary-rgb), 0.3);
      }

      .arc-progress[indeterminate] .progress__fill {
        width: 30% !important;
        animation: progress-indeterminate 1.5s ease-in-out infinite;
      }

      /* Spinner */
      .arc-progress .progress__spinner {
        display: inline-block;
      }

      .arc-progress[data-size="sm"] .progress__spinner { width: 20px; height: 20px; }
      .arc-progress:not([data-size]) .progress__spinner,
      .arc-progress[data-size="md"] .progress__spinner { width: 32px; height: 32px; }
      .arc-progress[data-size="lg"] .progress__spinner { width: 48px; height: 48px; }

      .arc-progress .progress__spinner svg {
        width: 100%;
        height: 100%;
        animation: spinner-rotate 1.4s linear infinite;
      }

      .arc-progress .progress__spinner-track {
        fill: none;
        stroke: var(--border-subtle);
        stroke-width: 3;
      }

      .arc-progress .progress__spinner-fill {
        fill: none;
        stroke: var(--accent-primary);
        stroke-width: 3;
        stroke-linecap: round;
        stroke-dasharray: 80, 200;
        stroke-dashoffset: 0;
        animation: spinner-dash 1.4s ease-in-out infinite;
      }

      .arc-progress .progress__header {
        display: flex;
        justify-content: space-between;
        align-items: baseline;
        margin-bottom: var(--space-xs);
      }

      .arc-progress .progress__value {
        font-family: var(--font-mono);
        font-size: var(--text-xs);
        color: var(--text-muted);
      }

      @keyframes progress-indeterminate {
        0%   { transform: translateX(-100%); }
        100% { transform: translateX(400%); }
      }

      @keyframes spinner-rotate {
        100% { transform: rotate(360deg); }
      }

      @keyframes spinner-dash {
        0%   { stroke-dasharray: 1, 200; stroke-dashoffset: 0; }
        50%  { stroke-dasharray: 80, 200; stroke-dashoffset: -35; }
        100% { stroke-dasharray: 80, 200; stroke-dashoffset: -125; }
      }

      @media (prefers-reduced-motion: reduce) {
        .arc-progress .progress__fill,
        .arc-progress .progress__spinner svg,
        .arc-progress .progress__spinner-fill {
          animation: none;
        }
      }

/* arc-tooltip */
.arc-tooltip {
        display: inline-block;
        position: relative;
      }

      .arc-tooltip .tooltip__trigger {
        display: inline-block;
      }

      .arc-tooltip .tooltip__popup {
        position: absolute;
        z-index: var(--z-tooltip);
        background: var(--surface-overlay);
        border: 1px solid var(--border-default);
        border-radius: var(--radius-sm);
        padding: var(--space-xs) var(--space-sm);
        font-family: var(--font-body);
        font-size: var(--text-sm);
        color: var(--text-primary);
        white-space: nowrap;
        pointer-events: none;
        opacity: 0;
        transition: opacity var(--transition-fast);
        box-shadow: var(--shadow-overlay);
        overflow: hidden;
      }

      .arc-tooltip .tooltip__popup::before {
        content: '';
        position: absolute;
        top: 0;
        left: 0;
        right: 0;
        height: 1px;
        background: var(--divider-glow);
      }

      .arc-tooltip .tooltip__popup.is-visible {
        opacity: 1;
      }

      /* Arrow */
      .arc-tooltip .tooltip__arrow {
        position: absolute;
        width: 8px;
        height: 8px;
        background: var(--surface-overlay);
        border: 1px solid var(--border-default);
        transform: rotate(45deg);
      }

      /* Positions */
      .arc-tooltip:not([data-position]) .tooltip__popup,
      .arc-tooltip[data-position="top"] .tooltip__popup {
        bottom: calc(100% + 8px);
        left: 50%;
        transform: translateX(-50%);
      }
      .arc-tooltip:not([data-position]) .tooltip__arrow,
      .arc-tooltip[data-position="top"] .tooltip__arrow {
        bottom: -5px;
        left: 50%;
        transform: translateX(-50%) rotate(45deg);
        border-top: none;
        border-left: none;
      }

      .arc-tooltip[data-position="bottom"] .tooltip__popup {
        top: calc(100% + 8px);
        left: 50%;
        transform: translateX(-50%);
      }
      .arc-tooltip[data-position="bottom"] .tooltip__arrow {
        top: -5px;
        left: 50%;
        transform: translateX(-50%) rotate(45deg);
        border-bottom: none;
        border-right: none;
      }

      .arc-tooltip[data-position="left"] .tooltip__popup {
        right: calc(100% + 8px);
        top: 50%;
        transform: translateY(-50%);
      }
      .arc-tooltip[data-position="left"] .tooltip__arrow {
        right: -5px;
        top: 50%;
        transform: translateY(-50%) rotate(45deg);
        border-bottom: none;
        border-left: none;
      }

      .arc-tooltip[data-position="right"] .tooltip__popup {
        left: calc(100% + 8px);
        top: 50%;
        transform: translateY(-50%);
      }
      .arc-tooltip[data-position="right"] .tooltip__arrow {
        left: -5px;
        top: 50%;
        transform: translateY(-50%) rotate(45deg);
        border-top: none;
        border-right: none;
      }

      @media (prefers-reduced-motion: reduce) {
        .arc-tooltip *,
        .arc-tooltip *::before,
        .arc-tooltip *::after {
          animation-duration: 0.01ms !important;
          animation-iteration-count: 1 !important;
          transition-duration: 0.01ms !important;
        }
      }