/* ==========================================================================
   ScheduleHub — Minimalist Modern CSS (No Emojis, Pure SVG & Strict Typography)
   ========================================================================== */

:root {
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --transition-speed: 0.18s;

  /* Dark Theme (Default) */
  --bg-main: #0b0f19;
  --bg-surface: #111827;
  --bg-surface-elevated: #1a2333;
  --bg-hover: #263346;
  --border-color: #243144;
  --border-subtle: #1e293b;
  
  --text-primary: #f8fafc;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;
  
  --accent: #6366f1;
  --accent-hover: #4f46e5;
  --accent-subtle: rgba(99, 102, 241, 0.12);
  --accent-text: #818cf8;

  --badge-cancel-bg: rgba(239, 68, 68, 0.15);
  --badge-cancel-text: #f87171;
  --badge-cancel-border: rgba(239, 68, 68, 0.3);

  --badge-change-bg: rgba(245, 158, 11, 0.15);
  --badge-change-text: #fbbf24;
  --badge-change-border: rgba(245, 158, 11, 0.3);

  --badge-today-bg: #4338ca;
  --badge-today-text: #ffffff;

  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.25);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.35), 0 2px 4px -1px rgba(0, 0, 0, 0.2);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.45), 0 4px 6px -2px rgba(0, 0, 0, 0.25);
}

[data-theme="light"] {
  --bg-main: #f8fafc;
  --bg-surface: #ffffff;
  --bg-surface-elevated: #f1f5f9;
  --bg-hover: #e2e8f0;
  --border-color: #cbd5e1;
  --border-subtle: #e2e8f0;

  --text-primary: #0f172a;
  --text-secondary: #475569;
  --text-muted: #94a3b8;

  --accent: #4f46e5;
  --accent-hover: #4338ca;
  --accent-subtle: rgba(79, 70, 229, 0.08);
  --accent-text: #4f46e5;

  --badge-cancel-bg: #fee2e2;
  --badge-cancel-text: #dc2626;
  --badge-cancel-border: #fca5a5;

  --badge-change-bg: #fef3c7;
  --badge-change-text: #d97706;
  --badge-change-border: #fcd34d;

  --badge-today-bg: #4f46e5;
  --badge-today-text: #ffffff;

  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.07), 0 2px 4px -1px rgba(0, 0, 0, 0.04);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.08), 0 4px 6px -2px rgba(0, 0, 0, 0.03);
}

/* Reset & Base */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

body {
  font-family: var(--font-sans);
  background-color: var(--bg-main);
  color: var(--text-primary);
  line-height: 1.5;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  -webkit-font-smoothing: antialiased;
  transition: background-color var(--transition-speed), color var(--transition-speed);
}

.container {
  max-width: 960px; /* Comfortable reading width for single column timeline */
  margin: 0 auto;
  padding: 0 1.25rem;
  width: 100%;
}

/* Typography */
h1, h2, h3, h4 {
  font-weight: 600;
  color: var(--text-primary);
}

.sub-text {
  font-size: 0.85rem;
  color: var(--text-muted);
}

.hidden {
  display: none !important;
}

.mt-4 { margin-top: 1rem; }

/* Header */
.site-header {
  background-color: var(--bg-surface);
  border-bottom: 1px solid var(--border-color);
  position: sticky;
  top: 0;
  z-index: 40;
  backdrop-filter: blur(8px);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 4.25rem;
  gap: 1rem;
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  font-weight: 700;
  font-size: 1.25rem;
  letter-spacing: -0.02em;
  color: var(--text-primary);
  text-decoration: none;
  cursor: pointer;
  user-select: none;
  transition: opacity var(--transition-speed);
}

.brand:hover {
  opacity: 0.85;
}

.brand-icon {
  width: 1.6rem;
  height: 1.6rem;
  color: var(--accent);
}

/* Navigation Tabs */
.nav-tabs {
  display: flex;
  gap: 0.35rem;
  background: var(--bg-surface-elevated);
  padding: 0.25rem;
  border-radius: 0.6rem;
  border: 1px solid var(--border-subtle);
}

.tab-btn {
  display: flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.45rem 0.95rem;
  border: none;
  background: transparent;
  color: var(--text-secondary);
  font-size: 0.92rem;
  font-weight: 500;
  border-radius: 0.45rem;
  cursor: pointer;
  transition: all var(--transition-speed);
}

.tab-btn:hover {
  color: var(--text-primary);
  background: var(--bg-hover);
}

.tab-btn.active {
  color: var(--text-primary);
  background: var(--bg-surface);
  box-shadow: var(--shadow-sm);
}

.tab-icon {
  width: 1.05rem;
  height: 1.05rem;
}

/* Controls */
.header-controls {
  display: flex;
  align-items: center;
  gap: 0.6rem;
}

.control-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.5rem 0.95rem;
  border: 1px solid var(--border-color);
  background: var(--bg-surface-elevated);
  color: var(--text-primary);
  font-size: 0.88rem;
  font-weight: 500;
  border-radius: 0.5rem;
  cursor: pointer;
  transition: all var(--transition-speed);
}

.control-btn:hover {
  background: var(--bg-hover);
  border-color: var(--text-muted);
}

.control-btn.icon-only {
  padding: 0.55rem;
}

.control-icon, .theme-icon, .chevron-icon {
  width: 1.15rem;
  height: 1.15rem;
}

[data-theme="dark"] .sun-icon { display: block; }
[data-theme="dark"] .moon-icon { display: none; }
[data-theme="light"] .sun-icon { display: none; }
[data-theme="light"] .moon-icon { display: block; }

/* Main Content Area */
.main-content {
  flex: 1;
  padding-top: 2rem;
  padding-bottom: 4rem;
}

.offline-banner {
  background: rgba(245, 158, 11, 0.15);
  border: 1px solid rgba(245, 158, 11, 0.35);
  color: #fbbf24;
  padding: 0.65rem 1rem;
  border-radius: 0.6rem;
  font-size: 0.85rem;
  font-weight: 500;
  display: flex;
  align-items: center;
  gap: 0.6rem;
  margin-bottom: 1.25rem;
}

.offline-icon {
  width: 1.2rem;
  height: 1.2rem;
  flex-shrink: 0;
}

.today-btn {
  background: var(--bg-surface-elevated);
  border: 1px solid var(--border-subtle);
  color: var(--text-primary);
  font-weight: 600;
  font-size: 0.82rem;
  padding: 0.35rem 0.75rem;
  border-radius: 0.4rem;
  cursor: pointer;
  transition: all var(--transition-speed);
}

.today-btn:hover {
  background: var(--bg-hover);
  border-color: var(--accent);
  color: var(--accent-text);
}

.pane-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 1.75rem;
  flex-wrap: wrap;
  gap: 1rem;
}

.pane-heading {
  font-size: 1.4rem;
}

/* Week Selector */
.week-selector {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  background: var(--bg-surface);
  padding: 0.85rem 1.5rem;
  border-radius: 0.75rem;
  border: 1px solid var(--border-color);
}

.week-info {
  text-align: center;
}

.week-heading {
  font-size: 1.15rem;
  font-weight: 600;
}

.week-dates-sub {
  font-size: 0.88rem;
  color: var(--text-secondary);
}

.action-btn {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.5rem 0.95rem;
  background: var(--bg-surface-elevated);
  border: 1px solid var(--border-color);
  color: var(--text-primary);
  border-radius: 0.5rem;
  font-size: 0.88rem;
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition-speed);
}

.action-btn:hover {
  background: var(--bg-hover);
}

.action-btn svg {
  width: 1rem;
  height: 1rem;
}

/* ==========================================================================
   Single Column Schedule (Vertical Timeline Stack)
   ========================================================================== */
.days-stack {
  display: flex;
  flex-direction: column;
  gap: 1.75rem;
}

.day-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: 0.85rem;
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
}

.day-card.today {
  border-color: var(--accent);
  box-shadow: 0 0 0 1px var(--accent);
}

.day-card-header {
  padding: 1rem 1.5rem;
  background: var(--bg-surface-elevated);
  border-bottom: 1px solid var(--border-subtle);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.day-card-title {
  font-size: 1.15rem;
  font-weight: 600;
  display: flex;
  align-items: center;
  gap: 0.6rem;
}

.day-today-badge {
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  background: var(--badge-today-bg);
  color: var(--badge-today-text);
  padding: 0.25rem 0.6rem;
  border-radius: 0.35rem;
}

.day-pairs-list {
  padding: 1.25rem 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

/* Pair Row — Spacious horizontal split */
.pair-row {
  display: flex;
  gap: 1.5rem;
  align-items: flex-start;
  padding-bottom: 1rem;
  border-bottom: 1px dashed var(--border-subtle);
}

.pair-row:last-child {
  padding-bottom: 0;
  border-bottom: none;
}

.pair-time-col {
  width: 6.5rem;
  flex-shrink: 0;
  display: flex;
  flex-direction: column;
  gap: 0.15rem;
}

.pair-num-badge {
  font-weight: 700;
  color: var(--accent-text);
  font-size: 0.95rem;
}

.pair-time-val {
  font-size: 0.82rem;
  color: var(--text-muted);
  font-variant-numeric: tabular-nums;
}

.pair-lessons-col {
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 0.65rem;
}

.lesson-box {
  background: var(--bg-surface-elevated);
  border: 1px solid var(--border-subtle);
  border-radius: 0.6rem;
  padding: 0.75rem 1rem;
  transition: transform var(--transition-speed), border-color var(--transition-speed);
}

.lesson-box:hover {
  border-color: var(--border-color);
}

.lesson-box.canceled {
  border-color: var(--badge-cancel-border);
  background: var(--badge-cancel-bg);
  text-decoration: line-through;
  opacity: 0.85;
}

.lesson-box.changed {
  border-color: var(--badge-change-border);
  background: var(--badge-change-bg);
}

.lesson-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 0.75rem;
  margin-bottom: 0.4rem;
}

.lesson-title {
  font-weight: 600;
  font-size: 1rem;
  color: var(--text-primary);
  line-height: 1.4;
}

.lesson-kind {
  font-size: 0.78rem;
  color: var(--text-muted);
  font-weight: 500;
  background: var(--bg-hover);
  padding: 0.15rem 0.45rem;
  border-radius: 0.3rem;
  white-space: nowrap;
}

.lesson-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 1.25rem;
  font-size: 0.85rem;
  color: var(--text-secondary);
  margin-top: 0.4rem;
}

.meta-item {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
}

.meta-icon {
  width: 0.95rem;
  height: 0.95rem;
  color: var(--text-muted);
}

.status-tag {
  font-size: 0.72rem;
  font-weight: 700;
  padding: 0.18rem 0.45rem;
  border-radius: 0.3rem;
  text-transform: uppercase;
}

.lesson-box.is-current {
  border-color: var(--accent);
  background: var(--bg-surface);
  box-shadow: 0 0 0 2px var(--accent-subtle);
  position: relative;
}

.status-tag.tag-current {
  background: rgba(16, 185, 129, 0.18);
  color: #34d399;
  border: 1px solid rgba(16, 185, 129, 0.4);
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
}

.status-tag.tag-current::before {
  content: "";
  display: inline-block;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: #10b981;
  box-shadow: 0 0 6px #10b981;
  animation: pulse-dot 1.5s infinite;
}

@keyframes pulse-dot {
  0% { transform: scale(0.9); opacity: 0.7; }
  50% { transform: scale(1.3); opacity: 1; }
  100% { transform: scale(0.9); opacity: 0.7; }
}

.status-tag.tag-canceled {
  background: var(--badge-cancel-bg);
  color: var(--badge-cancel-text);
  border: 1px solid var(--badge-cancel-border);
}

.status-tag.tag-changed {
  background: var(--badge-change-bg);
  color: var(--badge-change-text);
  border: 1px solid var(--badge-change-border);
}

.subgroup-tag {
  font-size: 0.75rem;
  background: var(--bg-hover);
  color: var(--text-secondary);
  padding: 0.15rem 0.45rem;
  border-radius: 0.3rem;
  font-weight: 500;
}

/* Empty / Free Day */
.free-day-text {
  color: var(--text-muted);
  font-size: 0.92rem;
  padding: 1.5rem 0;
  text-align: center;
  font-style: italic;
}

/* State Containers (Loading, Empty, Error) */
.state-container {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 4rem 1.5rem;
  text-align: center;
  background: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: 0.85rem;
}

.spinner {
  width: 2.2rem;
  height: 2.2rem;
  border: 3px solid var(--border-color);
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spin 0.7s linear infinite;
  margin-bottom: 1rem;
}

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

.empty-icon {
  width: 3rem;
  height: 3rem;
  color: var(--text-muted);
  margin-bottom: 1rem;
}

/* Tab 2: Changes */
.changes-container {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.changes-date-section {
  background: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: 0.85rem;
  overflow: hidden;
  margin-bottom: 1.75rem;
}

.changes-date-header {
  padding: 1rem 1.5rem;
  background: var(--bg-surface-elevated);
  border-bottom: 1px solid var(--border-subtle);
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.changes-date-title {
  font-size: 1.15rem;
  font-weight: 600;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  gap: 0.6rem;
}

.changes-date-icon {
  width: 1.25rem;
  height: 1.25rem;
  color: var(--accent);
}

.changes-groups-stack {
  padding: 1.25rem 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.change-group-card {
  background: var(--bg-surface-elevated);
  border: 1px solid var(--border-subtle);
  border-radius: 0.75rem;
  overflow: hidden;
}

.change-group-header {
  padding: 0.9rem 1.25rem;
  background: var(--bg-surface-elevated);
  font-weight: 600;
  font-size: 1.05rem;
  border-bottom: 1px solid var(--border-subtle);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.change-group-header.clickable {
  cursor: pointer;
  user-select: none;
  transition: background var(--transition-speed), color var(--transition-speed);
}

.change-group-header.clickable:hover {
  background: var(--bg-hover);
  color: var(--accent-text);
}

.changes-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.88rem;
}

.changes-table th, .changes-table td {
  padding: 0.75rem 1rem;
  text-align: left;
  border-bottom: 1px solid var(--border-subtle);
}

.changes-table th {
  color: var(--text-muted);
  font-weight: 600;
  background: var(--bg-surface);
}

.change-diff-del {
  color: var(--badge-cancel-text);
  text-decoration: line-through;
}

.change-diff-add {
  color: var(--badge-change-text);
  font-weight: 600;
}

/* Tab 3: Search */
.search-header-box {
  display: flex;
  flex-direction: column;
  gap: 0.85rem;
  margin-bottom: 1.75rem;
}

.search-input-wrapper {
  position: relative;
  width: 100%;
}

.search-input-icon {
  position: absolute;
  left: 1.15rem;
  top: 50%;
  transform: translateY(-50%);
  width: 1.3rem;
  height: 1.3rem;
  color: var(--text-muted);
  pointer-events: none;
}

#global-search-input {
  width: 100%;
  padding: 0.95rem 3rem 0.95rem 3.2rem;
  background: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: 0.75rem;
  color: var(--text-primary);
  font-size: 1.05rem;
  outline: none;
  transition: border-color var(--transition-speed);
}

#global-search-input:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-subtle);
}

.clear-btn {
  position: absolute;
  right: 0.95rem;
  top: 50%;
  transform: translateY(-50%);
  background: transparent;
  border: none;
  color: var(--text-muted);
  cursor: pointer;
  padding: 0.35rem;
  display: flex;
  align-items: center;
  justify-content: center;
}

.clear-btn svg {
  width: 1.1rem;
  height: 1.1rem;
}

.search-chips {
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
}

.chip-btn {
  padding: 0.4rem 0.95rem;
  border-radius: 2rem;
  border: 1px solid var(--border-color);
  background: var(--bg-surface);
  color: var(--text-secondary);
  font-size: 0.85rem;
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition-speed);
}

.chip-btn:hover {
  background: var(--bg-hover);
  color: var(--text-primary);
}

.chip-btn.active {
  background: var(--accent);
  border-color: var(--accent);
  color: #ffffff;
}

/* Search Suggestions Dropdown */
.search-suggestions-dropdown {
  position: absolute;
  top: calc(100% + 0.5rem);
  left: 0;
  right: 0;
  background: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: 0.75rem;
  box-shadow: var(--shadow-lg);
  z-index: 50;
  max-height: 380px;
  overflow-y: auto;
}

.suggestion-section-title {
  padding: 0.6rem 1rem 0.3rem 1rem;
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
  background: var(--bg-surface-elevated);
}

.suggestion-item {
  padding: 0.65rem 1.25rem;
  font-size: 0.92rem;
  color: var(--text-primary);
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 0.6rem;
  border-bottom: 1px solid var(--border-subtle);
  transition: background var(--transition-speed);
}

.suggestion-item:last-child {
  border-bottom: none;
}

.suggestion-item:hover, .suggestion-item.selected {
  background: var(--bg-hover);
  color: var(--accent-text);
}

.suggestion-icon {
  width: 1rem;
  height: 1rem;
  color: var(--text-muted);
  flex-shrink: 0;
}

.search-results-stack {
  display: flex;
  flex-direction: column;
  gap: 1.75rem;
}

.search-result-group-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: 0.85rem;
  overflow: hidden;
  box-shadow: var(--shadow-sm);
}

.search-result-header {
  padding: 1rem 1.5rem;
  background: var(--bg-surface-elevated);
  border-bottom: 1px solid var(--border-subtle);
}

.search-result-title {
  font-size: 1.15rem;
  font-weight: 600;
}

.search-result-days-container {
  padding: 1.25rem 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 1.25rem;
}

.search-day-block {
  border-left: 3px solid var(--accent);
  padding-left: 1rem;
}

.search-day-title {
  font-weight: 600;
  font-size: 1rem;
  margin-bottom: 0.5rem;
  color: var(--accent-text);
}

.search-lessons-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.88rem;
}

.search-lessons-table td {
  padding: 0.5rem 0.65rem;
  border-bottom: 1px solid var(--border-subtle);
}

.search-group-badge {
  color: var(--accent-text);
  font-weight: 600;
  cursor: pointer;
  padding: 0.2rem 0.5rem;
  border-radius: 0.35rem;
  display: inline-block;
  user-select: none;
  transition: all var(--transition-speed);
}

.search-group-badge:hover {
  background: var(--accent-subtle);
  color: var(--accent);
  text-decoration: underline;
}

/* Modals & Custom Combobox */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.65);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 60;
  padding: 1rem;
  backdrop-filter: blur(5px);
}

.modal-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: 0.85rem;
  width: 100%;
  max-width: 460px;
  box-shadow: var(--shadow-lg);
  display: flex;
  flex-direction: column;
  overflow: visible; /* To allow combobox dropdown to show */
  position: relative;
}

.modal-header {
  padding: 1.1rem 1.5rem;
  border-bottom: 1px solid var(--border-subtle);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.modal-title {
  font-size: 1.15rem;
  font-weight: 600;
}

.modal-body {
  padding: 1.5rem;
}

.form-label {
  display: block;
  font-size: 0.88rem;
  font-weight: 500;
  color: var(--text-secondary);
  margin-bottom: 0.5rem;
}

.combobox-wrapper {
  position: relative;
  width: 100%;
}

.combobox-wrapper input {
  width: 100%;
  padding: 0.75rem 1rem;
  border: 1px solid var(--border-color);
  border-radius: 0.55rem;
  background: var(--bg-surface-elevated);
  color: var(--text-primary);
  font-size: 1rem;
  outline: none;
  transition: border-color var(--transition-speed);
}

.combobox-wrapper input:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 2px var(--accent-subtle);
}

.combobox-dropdown {
  position: absolute;
  top: calc(100% + 0.35rem);
  left: 0;
  right: 0;
  background: var(--bg-surface);
  border: 1px solid var(--border-color);
  border-radius: 0.55rem;
  max-height: 220px;
  overflow-y: auto;
  z-index: 70;
  box-shadow: var(--shadow-lg);
}

.combobox-item {
  padding: 0.6rem 1rem;
  font-size: 0.92rem;
  color: var(--text-primary);
  cursor: pointer;
  border-bottom: 1px solid var(--border-subtle);
  transition: background var(--transition-speed);
}

.combobox-item:last-child {
  border-bottom: none;
}

.combobox-item:hover, .combobox-item.active {
  background: var(--accent);
  color: #ffffff;
}

.subgroup-selector {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0.6rem;
}

.subgroup-btn {
  padding: 0.55rem;
  border: 1px solid var(--border-color);
  background: var(--bg-surface-elevated);
  color: var(--text-secondary);
  border-radius: 0.45rem;
  font-size: 0.88rem;
  font-weight: 500;
  cursor: pointer;
}

.subgroup-btn.active {
  background: var(--accent);
  border-color: var(--accent);
  color: #ffffff;
}

.modal-footer {
  padding: 1.1rem 1.5rem;
  border-top: 1px solid var(--border-subtle);
  background: var(--bg-surface-elevated);
  border-bottom-left-radius: 0.85rem;
  border-bottom-right-radius: 0.85rem;
}

.primary-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.7rem 1.35rem;
  background: var(--accent);
  color: #ffffff;
  border: none;
  border-radius: 0.5rem;
  font-size: 0.95rem;
  font-weight: 600;
  cursor: pointer;
  transition: background var(--transition-speed);
}

.primary-btn:hover {
  background: var(--accent-hover);
}

.w-full {
  width: 100%;
}

.icon-btn {
  background: transparent;
  border: none;
  color: var(--text-muted);
  cursor: pointer;
  padding: 0.35rem;
  display: flex;
  align-items: center;
  justify-content: center;
}

.icon-btn:hover {
  color: var(--text-primary);
}

.icon-btn svg {
  width: 1.25rem;
  height: 1.25rem;
}

/* Responsive adjustments */
@media (max-width: 640px) {
  .header-inner {
    height: auto;
    padding: 0.75rem 0;
    flex-wrap: wrap;
  }
  .nav-tabs {
    order: 3;
    width: 100%;
    justify-content: space-between;
  }
  .tab-btn {
    flex: 1;
    justify-content: center;
    padding: 0.4rem 0.5rem;
    font-size: 0.82rem;
  }
  .pair-row {
    flex-direction: column;
    gap: 0.5rem;
  }
  .pair-time-col {
    width: 100%;
    flex-direction: row;
    justify-content: space-between;
    align-items: center;
  }
}