:root,
.theme-light {
  --background-color: #f7fafc;
  --text-color: #2d3748;
  --border-color: #edf2f7;
  --primary-color: #4b6cb7;
  --accent-color: #48bb78;
  --disabled-color: #a0aec0;
  --hover-bg: #e6edf2;
  --selected-bg: #024575;
  --today-bg: #1662d4;
  --holiday-bg: #f59e0b;
  --event-meeting-bg: #22c55e;
  --event-holiday-bg: #f43f5e;
  --disabled-bg: #ffffff;
  --disabled-text: #6b6868;
  --shadow-color: rgba(0, 0, 0, 0.1);
  --range-preview-bg: rgba(2, 69, 117, 0.3);
  --range-hover-bg: rgba(2, 69, 117, 0.4);
  --range-end-bg: rgba(2, 69, 117, 0.6);
  --in-range-bg: rgba(2, 69, 117, 0.2);
  --today-underline: #024575;
  --back-button-bg: #4b6cb7;
  --back-button-hover: #2a4365;
}

.theme-dark {
  --background-color: #1a202c;
  --text-color: #e2e8f0;
  --border-color: #4a5568;
  --primary-color: #63b3ed;
  --accent-color: #68d391;
  --disabled-color: #718096;
  --hover-bg: #2d3748;
  --selected-bg: #2b6cb0;
  --today-bg: #2b6cb0;
  --holiday-bg: #f6ad55;
  --event-meeting-bg: #38a169;
  --event-holiday-bg: #f56565;
  --disabled-bg: #2d3748;
  --disabled-text: #a0aec0;
  --shadow-color: rgba(0, 0, 0, 0.3);
  --range-preview-bg: rgba(99, 179, 237, 0.3);
  --range-hover-bg: rgba(99, 179, 237, 0.4);
  --range-end-bg: rgba(99, 179, 237, 0.6);
  --in-range-bg: rgba(99, 179, 237, 0.2);
  --today-underline: #63b3ed;
  --back-button-bg: #63b3ed;
  --back-button-hover: #4299e1;
}

.calendar {
  max-width: 100%;
  margin: 8px;
  padding: 0;
  font-family:
    "Poppins",
    -apple-system,
    BlinkMacSystemFont,
    "Segoe UI",
    Roboto,
    sans-serif;
  background: var(--background-color);
  border-radius: 10px;
  box-shadow: 0 4px 12px var(--shadow-color);
  color: var(--text-color);
}

/* Focus state */
.calendar:focus {
  box-shadow: 0 0 0 4px rgba(75, 108, 183, 0.3);
  outline: none;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  border: 0;
}

/* ========== Header ========== */
.header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1.5rem 2rem;
  background: var(--background-color);
  border-bottom: 1px solid var(--border-color);
  flex-wrap: wrap;
  gap: 1.5rem;
}

.header-month-section {
  display: flex;
  align-items: center;
  gap: 1.5rem;
}

.header-month-nav {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.header-month-label {
  font-size: 1.5rem;
  font-weight: 600;
  color: var(--text-color);
  text-transform: capitalize;
  letter-spacing: 0.05rem;
}

.nav-button {
  width: 2.75rem;
  height: 2.75rem;
  border: none;
  background: var(--hover-bg);
  color: var(--text-color);
  border-radius: 50%;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.3s ease-in-out;
}

.nav-button:hover {
  background: var(--primary-color);
  color: #ffffff;
  transform: scale(1.1);
}

.nav-button:disabled {
  background: var(--disabled-bg);
  color: var(--disabled-color);
  opacity: 0.6;
  cursor: not-allowed;
  transform: none;
}

/* ========== Year Dropdown ========== */
.header-year-section {
  position: relative;
  display: flex;
  align-items: center;
}

.year-select-wrapper {
  padding: 0.75rem 2.5rem 0.75rem 1.25rem;
  font-size: 1.1rem;
  border: 1px solid var(--border-color);
  border-radius: 10px;
  background: var(--background-color);
  color: var(--text-color);
  cursor: pointer;
  display: flex;
  align-items: center;
  position: relative;
  transition: all 0.3s ease-in-out;
}

.year-select-wrapper:hover,
.year-select-wrapper:focus,
.year-select-wrapper[aria-expanded="true"] {
  border-color: var(--accent-color);
  box-shadow: 0 0 0 3px rgba(75, 108, 183, 0.2);
}

.year-select-display {
  font-weight: 500;
}

.chevron-down {
  position: absolute;
  right: 1rem;
  font-size: 1.2rem;
  color: var(--text-color);
  pointer-events: none;
  transition: transform 0.3s ease-in-out;
}

.year-select-wrapper[aria-expanded="true"] .chevron-down {
  transform: rotate(180deg);
}

.year-dropdown {
  position: absolute;
  top: calc(100% + 0.75rem);
  right: 0;
  width: 250px;
  max-height: 320px;
  background: var(--background-color);
  border: 1px solid var(--border-color);
  border-radius: 10px;
  box-shadow: 0 8px 24px var(--shadow-color);
  z-index: 1000;
  animation: slideIn 0.3s ease-in-out;
  overflow: hidden;
}

@keyframes slideIn {
  from {
    transform: translateY(-20px);
    opacity: 0;
  }
  to {
    transform: translateY(0);
    opacity: 1;
  }
}

.year-search {
  width: 100%;
  padding: 0.75rem 1rem;
  border: none;
  border-bottom: 2px solid var(--border-color);
  font-size: 1rem;
  color: var(--text-color);
  background: transparent;
  outline: none;
  transition: all 0.3s ease-in-out;
}

.year-search:focus {
  border-bottom-color: var(--accent-color);
}

.year-list {
  max-height: 150px;
  overflow-y: auto;
  scrollbar-width: thin;
  scrollbar-color: var(--primary-color) var(--hover-bg);
  padding: 0.5rem 0;
}

.year-list::-webkit-scrollbar {
  width: 8px;
}

.year-list::-webkit-scrollbar-track {
  background: var(--hover-bg);
  border-radius: 4px;
}

.year-list::-webkit-scrollbar-thumb {
  background: var(--primary-color);
  border-radius: 4px;
}

.year-option {
  display: block;
  width: 100%;
  padding: 0.75rem 1.25rem;
  border: none;
  background: transparent;
  font-size: 1rem;
  color: var(--text-color);
  text-align: left;
  cursor: pointer;
  transition: all 0.3s ease-in-out;
}

.year-option:hover,
.year-option.focused {
  background: var(--hover-bg);
  color: var(--text-color);
  transform: translateX(8px);
  border-radius: 6px;
}

.year-option.current-year {
  background: var(--selected-bg);
  color: #ffffff;
  font-weight: 600;
  border-radius: 6px;
}

.year-option:focus {
  outline: none;
  box-shadow: 0 0 0 2px rgba(2, 69, 117, 0.2);
}

.year-option:disabled {
  color: var(--disabled-color);
  cursor: not-allowed;
  background: var(--disabled-bg);
  opacity: 0.6;
}

.year-option:disabled:hover,
.year-option:disabled.focused {
  background: var(--disabled-bg);
  color: var(--disabled-color);
  transform: none;
}

/* ========== Weekday Row ========== */
.calendar-weekdays {
  display: grid;
  grid-template-columns: repeat(7, 1fr);
  background: var(--background-color);
  padding: 0.75rem 0;
  border-bottom: 2px solid var(--border-color);
}

.weekday {
  text-align: center;
  font-weight: 600;
  color: var(--disabled-color);
  padding: 0.5rem;
  font-size: 0.9rem;
  text-transform: uppercase;
  transition: all 0.3s ease-in-out;
}

.weekday.saturday,
.weekday.sunday {
  color: #e53e3e;
}

.weekday:hover {
  color: var(--text-color);
  background: var(--hover-bg);
  border-radius: 6px;
}

/* ========== Calendar Grid ========== */
.calendar-days {
  display: grid;
  grid-template-columns: repeat(7, 1fr);
  background: var(--background-color);
  padding: 0.75rem;
  gap: 0.25rem;
}

/* ========== Base Day Style ========== */
.calendar-day {
  width: 40px;
  height: 40px;
  margin: 0;
  padding: 8px;
  border: none;
  background: var(--background-color);
  cursor: pointer;
  text-align: center;
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--text-color);
  transition: all 0.3s ease-in-out;
  min-height: 3.5rem;
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
}

.calendar-day:hover {
  background: var(--hover-bg);
  color: var(--primary-color);
  transform: scale(1.05);
}

/* ========== Today Highlight ========== */
.calendar-day.today {
  background: var(--today-bg);
  color: #ffffff;
  font-weight: 700;
  border-radius: 8px;
  box-shadow: 0 2px 6px var(--shadow-color);
}

.calendar-day.today::after {
  content: "";
  position: absolute;
  bottom: 6px;
  left: 30%;
  width: 40%;
  height: 1px;
  background-color: var(--today-underline);
  border-radius: 2px;
}

.calendar-day.today:hover {
  background: var(--primary-color);
  transform: scale(1.1);
}

.calendar-day.saturday,
.calendar-day.sunday {
  color: #e53e3e;
}

.calendar-day.saturday:hover,
.calendar-day.sunday:hover {
  background: var(--hover-bg);
}

/* ========== Start/End Dates ========== */
.calendar-day.selected,
.calendar-day.selected-start,
.calendar-day.selected-end {
  background: var(--selected-bg);
  color: #ffffff;
  font-weight: 700;
  border-radius: 8px;
  box-shadow: 0 2px 6px var(--shadow-color);
  border: 1px solid var(--primary-color);
  z-index: 2;
}

.calendar-day.selected-start:hover,
.calendar-day.selected-end:hover {
  background: var(--primary-color);
  transform: scale(1.1);
}

.calendar-day.selected-end.in-range,
.calendar-day.selected-start.in-range {
  background: var(--selected-bg);
  border-radius: 8px;
  z-index: 3;
}

/* ========== Start/End Circle Marker ========== */
.calendar-day.selected-start::after,
.calendar-day.selected-end::after {
  content: "";
  position: absolute;
  width: 10px;
  height: 10px;
  background: #ffffff;
  border-radius: 50%;
  border: 2px solid var(--selected-bg);
  top: 50%;
  transform: translateY(-50%);
}

.calendar-day.selected-start::after {
  left: 4px;
}

.calendar-day.selected-end::after {
  right: 4px;
}

.calendar-day.in-range {
  background: var(--in-range-bg);
  color: var(--text-color);
  border-radius: 0;
  transition: all 0.3s ease-in-out;
  border-left: 1px solid var(--border-color);
  border-right: 1px solid var(--border-color);
  position: relative;
  z-index: 1;
}

.calendar-day.in-range + .calendar-day.in-range {
  border-left: none;
}

.calendar-day.in-range:first-child {
  border-left: 1px solid var(--border-color);
}

.calendar-day.in-range:last-child {
  border-right: 1px solid var(--border-color);
}

.calendar-day.in-range:hover {
  background: var(--range-hover-bg);
}

/* ========== Hovered Future Range Preview ========== */
.calendar-day.range-preview {
  background: var(--range-preview-bg);
  color: var(--text-color);
  border-radius: 0;
  z-index: 1;
  transition: all 0.3s ease-in-out;
}

.calendar-day.range-preview:hover {
  background: var(--range-hover-bg);
}

/* ========== Hover Range End ========== */
.calendar-day.hover-range-end {
  background: var(--range-end-bg);
  color: #ffffff;
  border-radius: 8px;
  z-index: 2;
  transform: scale(1.05);
}

/* ========== Hover Range General ========== */
.calendar-day.hover-range {
  background: var(--range-hover-bg);
  color: #ffffff;
  border-radius: 8px;
  z-index: 2;
  transform: scale(1.05);
}

/* ========== Disabled Dates ========== */
.calendar-day:disabled {
  background: var(--disabled-bg);
  color: var(--disabled-text);
  cursor: not-allowed;
  opacity: 0.6 !important;
}

.calendar-day:disabled.today,
.calendar-day:disabled.selected-start,
.calendar-day:disabled.selected-end {
  opacity: 0.6 !important;
}

.calendar-day:disabled:hover {
  background: var(--disabled-bg);
  color: var(--disabled-text);
  transform: none;
}

/* ========== Animation ========== */
.calendar-container {
  display: flex;
  gap: 12px;
  padding: 0;
  margin: 4px;
  justify-content: space-between;
  animation: fadeIn 0.4s ease-in-out;
  background: none;
}

@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* ========== Adjacent Month Dates ========== */
.calendar-day.adjacent-month {
  color: var(--disabled-text);
  font-weight: 300;
}

.calendar-day.adjacent-month:hover {
  color: var(--text-color);
}

/* Event Indicators */
.calendar-day.has-event::before {
  content: "";
  position: absolute;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--accent-color);
  bottom: 6px;
  right: 6px;
}

.event-indicator {
  font-size: 0.8rem;
  font-weight: 500;
  color: var(--text-color);
}

/* Day View */
.day-view {
  padding: 1.5rem;
  background: var(--background-color);
  border-radius: 0 0 10px 10px;
}

.day-detail {
  width: 100%;
  padding: 1rem;
  border: none;
  background: var(--background-color);
  border: 1px solid var(--border-color);
  border-radius: 10px;
  text-align: center;
  font-size: 1.1rem;
  font-weight: 600;
  color: var(--text-color);
  transition: all 0.3s ease-in-out;
  box-shadow: 0 2px 8px var(--shadow-color);
}

.day-detail.today {
  background: var(--today-bg);
  color: #ffffff;
  border: none;
}

.day-detail:hover {
  background: var(--hover-bg);
  transform: scale(1.02);
}

.day-detail.today:hover {
  background: var(--primary-color);
}

.day-detail:disabled {
  background: var(--disabled-bg);
  color: var(--disabled-color);
  cursor: not-allowed;
}

.day-detail-content {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.day-detail-date {
  font-size: 1.25rem;
  font-weight: 700;
}

.day-detail-events {
  font-size: 0.9rem;
  color: var(--disabled-color);
}

/* Year View */
.year-view {
  padding: 1.5rem;
  background: var(--background-color);
}

.year-view-list {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(100px, 1fr));
  gap: 0.5rem;
}

.year-month {
  padding: 0.75rem;
  border: none;
  background: var(--hover-bg);
  border-radius: 10px;
  text-align: center;
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-color);
  cursor: pointer;
  transition: all 0.3s ease-in-out;
  box-shadow: 0 2px 6px var(--shadow-color);
}

.year-month:hover {
  background: var(--primary-color);
  color: #ffffff;
  transform: translateY(-3px);
}

.year-month.selected {
  background: var(--selected-bg);
  color: #ffffff;
  font-weight: 700;
  box-shadow: 0 2px 8px var(--shadow-color);
}

.year-month.adjacent-year {
  opacity: 0.7;
}

.year-month:disabled {
  background: var(--disabled-color);
  color: #ffffff;
  cursor: not-allowed;
  opacity: 0.6;
}

.month-content {
  display: inline-block;
  transition: transform 0.2s ease;
}

.year-month:hover .month-content {
  transform: scale(1.1);
}

/* Holiday Styling */
.calendar-day.holiday {
  background: var(--holiday-bg);
  color: #ffffff;
  font-weight: 700;
  border-radius: 8px;
}

/* Custom Event Types */
.calendar-day.event-meeting::before {
  background: var(--event-meeting-bg);
}

.calendar-day.event-holiday::before {
  background: var(--event-holiday-bg);
}

/* Back Button */
.back-button {
  background: var(--back-button-bg);
  color: #ffffff;
  border: none;
  padding: 0.75rem 1.5rem;
  border-radius: 10px;
  cursor: pointer;
  margin: 1rem;
  transition: all 0.3s ease-in-out;
}

.back-button:hover {
  background: var(--back-button-hover);
  transform: translateY(-2px);
}

/* Double View */
.double-view .calendar-instance {
  width: 48%;
  flex: 1;
}

.calendar.double-view {
  max-width: 1400px;
  padding: 0 1.5rem;
}

/* Responsive Design */
@media (max-width: 900px) {
  .double-view .calendar-instance {
    width: 100%;
    max-width: 500px;
  }

  .calendar-container {
    flex-direction: column;
    align-items: center;
    gap: 1.5rem;
  }

  .calendar {
    max-width: 100%;
    margin: 8px;
  }

  .header {
    padding: 8px 12px;
    flex-wrap: wrap;
  }

  .calendar-day {
    width: 36px;
    height: 36px;
    font-size: 12px;
  }

  .year-view-list {
    grid-template-columns: repeat(2, 1fr);
  }

  .year-dropdown {
    width: 180px;
  }

  .year-select-wrapper {
    min-width: 80px;
  }
}

@media (max-width: 600px) {
  .year-view-list {
    grid-template-columns: repeat(2, 1fr);
  }

  .header-month-label {
    font-size: 1rem;
  }

  .year-select-wrapper {
    font-size: 0.9rem;
    padding: 0.5rem 1.5rem 0.5rem 1rem;
  }

  .year-dropdown {
    width: 180px;
  }

  .calendar-day {
    font-size: 0.85rem;
    min-height: 3rem;
  }
}