/* Register custom property so CSS can animate angle smoothly */
    @property --gradient-angle {
      syntax: "<angle>";
      initial-value: 0deg;
      inherits: false;
    }

    /* body {
      background-color: #09090b;
      color: #f4f4f5;
      font-family: system-ui, -apple-system, sans-serif;
      display: flex;
      justify-content: center;
      align-items: center;
      min-height: 100vh;
      margin: 0;
    } */

    /* Container holding border and child content */
    .shine-container {
      position: relative;
      display: inline-block;
      border-radius: 12px;
      padding: 1.5px; /* Border thickness */
      background: #27272a; /* Fallback static border */
      overflow: hidden;
    }

    /* The glowing animated border pseudo-element */
    .shine-container::before {
      content: "";
      position: absolute;
      inset: -150%; /* Extended boundaries prevent clipped gradient edges during rotation */
      
      /* Dynamic conic gradient length based on --shine-length variable */
      background: conic-gradient(
        from var(--gradient-angle),
        transparent 0%,
        transparent calc(100% - var(--shine-length, 30%)),
        var(--shine-color, #3b82f6) 100%
      );
      animation: shine-spin 4s linear infinite;
      z-index: 0;
    }

    /* Inner mask layer wrapping user children */
    .shine-content {
      position: relative;
      z-index: 1;
      border-radius: 10.5px; /* Keeps inner corners smooth relative to outer padding */
      background-color: #18181b;
      height: 100%;
      width: 100%;
    }

    @keyframes shine-spin {
      0% {
        --gradient-angle: 0deg;
      }
      100% {
        --gradient-angle: 360deg;
      }
    }

    /* Demo card content styling */
    .card {
      padding: 24px 32px;
      text-align: center;
    }
    .card h2 {
      margin: 0 0 8px 0;
      font-size: 1.25rem;
    }
    .card p {
      margin: 0;
      color: #a1a1aa;
      font-size: 0.9rem;
    }