/* ============================================================================
   UI/UX PRO MAX DESIGN SYSTEM EXTENSIONS & COMPONENT ALIASES
   ============================================================================ */

/* Text Utilities & Contrast Enhancements */
.text-muted {
  color: var(--text-muted, #71717a) !important;
}

[data-theme="light"] .text-muted {
  color: #52525b !important;
}

.text-accent {
  color: var(--accent-blue, #3b82f6) !important;
}

.user-dropdown-container {
  position: relative;
}

.subject-name-label {
  font-weight: 500;
  font-size: 0.88rem;
}

.zen-btn-label,
.nav-lb-label,
.zen-exit-label {
  font-size: 0.82rem;
  font-weight: 500;
  letter-spacing: 0.01em;
}

.streak-count {
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.02em;
}

/* Overview: Target Progress Card & Stats */
.target-progress-card {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.target-progress-body {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

/* Heatmap Grid & Legend */
.activity-heatmap-card {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.heatmap-grid {
  display: flex;
  gap: 3px;
  align-items: flex-end;
}

.heatmap-footer,
.heatmap-footer-legend {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 8px;
  font-size: 0.75rem;
  color: var(--text-muted);
  margin-top: 10px;
}

.heatmap-legend-label {
  font-size: 0.72rem;
  color: var(--text-muted);
  font-weight: 500;
}

.heatmap-scale-row {
  display: flex;
  align-items: center;
  gap: 3px;
}

.scale-box {
  width: 10px;
  height: 10px;
  border-radius: 2px;
  display: inline-block;
  transition: transform 0.15s ease;
}

.scale-box:hover {
  transform: scale(1.2);
}

.scale-box.level-0, .scale-box.lvl-0 { background: var(--bg-subtle, rgba(255, 255, 255, 0.06)); }
.scale-box.level-1, .scale-box.lvl-1 { background: #0e4429; }
.scale-box.level-2, .scale-box.lvl-2 { background: #006d32; }
.scale-box.level-3, .scale-box.lvl-3 { background: #26a641; }
.scale-box.level-4, .scale-box.lvl-4 { background: #39d353; box-shadow: 0 0 6px rgba(57, 211, 83, 0.4); }

[data-theme="light"] .scale-box.level-0, [data-theme="light"] .scale-box.lvl-0 { background: #ebedf0; }
[data-theme="light"] .scale-box.level-1, [data-theme="light"] .scale-box.lvl-1 { background: #9be9a8; }
[data-theme="light"] .scale-box.level-2, [data-theme="light"] .scale-box.lvl-2 { background: #40c463; }
[data-theme="light"] .scale-box.level-3, [data-theme="light"] .scale-box.lvl-3 { background: #30a14e; }
[data-theme="light"] .scale-box.level-4, [data-theme="light"] .scale-box.lvl-4 { background: #216e39; }

/* Calendar & History Timeline */
.calendar-card {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.calendar-nav-row,
.calendar-header-nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 8px;
}

.calendar-month-title,
.cal-month-title {
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--text-primary);
  letter-spacing: -0.01em;
}

.calendar-weekdays-header,
.cal-weekdays-grid {
  display: grid;
  grid-template-columns: repeat(7, 1fr);
  text-align: center;
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  padding-bottom: 6px;
  border-bottom: 1px solid var(--border-subtle);
}

.calendar-days-grid,
.cal-days-grid {
  display: grid;
  grid-template-columns: repeat(7, 1fr);
  gap: 6px;
  margin-top: 8px;
}

.calendar-footer-summary,
.cal-month-summary-row {
  display: flex;
  align-items: center;
  justify-content: flex-start;
  gap: 10px;
  margin-top: 14px;
  padding-top: 12px;
  border-top: 1px solid var(--border-subtle);
  flex-wrap: wrap;
}

.chip-goals,
.cal-summary-chip.goals-met {
  background: rgba(16, 185, 129, 0.12);
  color: #10b981;
  border: 1px solid rgba(16, 185, 129, 0.25);
  font-size: 0.78rem;
  font-weight: 600;
  padding: 4px 10px;
  border-radius: 9999px;
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

.chip-hours,
.cal-summary-chip.total-study {
  background: rgba(59, 130, 246, 0.12);
  color: #3b82f6;
  border: 1px solid rgba(59, 130, 246, 0.25);
  font-size: 0.78rem;
  font-weight: 600;
  padding: 4px 10px;
  border-radius: 9999px;
  display: inline-flex;
  align-items: center;
  gap: 4px;
}

.timeline-card {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.timeline-count-badge,
.sessions-count-badge {
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--text-muted);
  background: var(--bg-subtle, rgba(255, 255, 255, 0.05));
  padding: 3px 8px;
  border-radius: 9999px;
  border: 1px solid var(--border-subtle);
}

.timeline-list,
.timeline-list-container {
  display: flex;
  flex-direction: column;
  gap: 8px;
  max-height: 380px;
  overflow-y: auto;
  padding-right: 4px;
}

/* Daily Planner & Goals */
.planner-card {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.planner-stats-bar {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
  padding: 10px 14px;
  background: var(--bg-subtle, rgba(255, 255, 255, 0.03));
  border: 1px solid var(--border-subtle);
  border-radius: 12px;
}

.planner-stat-chip {
  display: flex;
  align-items: center;
  gap: 8px;
}

.stat-chip-label {
  font-size: 0.78rem;
  color: var(--text-muted);
  font-weight: 500;
}

.stat-chip-val {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--text-primary);
}

.planner-goals-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

/* Modals & Form Elements */
.modal-card-md {
  max-width: 580px;
}

.form-input {
  width: 100%;
  padding: 10px 14px;
  border-radius: 10px;
  border: 1px solid var(--border-subtle);
  background: var(--bg-input, rgba(255, 255, 255, 0.05));
  color: var(--text-primary);
  font-size: 0.9rem;
  outline: none;
  transition: border-color 0.15s ease, box-shadow 0.15s ease;
}

.form-input:focus {
  border-color: var(--accent-blue);
  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.2);
}

.input-label {
  display: block;
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--text-secondary);
  margin-bottom: 6px;
}

.input-optional {
  font-size: 0.75rem;
  font-weight: 400;
  color: var(--text-muted);
  margin-left: 4px;
}

.toggle-text {
  font-size: 0.88rem;
  font-weight: 500;
  color: var(--text-primary);
}

.btn-ghost {
  background: transparent;
  border: 1px solid transparent;
  color: var(--text-muted);
  cursor: pointer;
  border-radius: 8px;
  padding: 6px 12px;
  font-size: 0.85rem;
  transition: all 0.15s ease;
}

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

.footer-copy {
  font-size: 0.8rem;
  color: var(--text-muted);
}

.footer-link {
  color: var(--text-muted);
  text-decoration: none;
  transition: color 0.15s ease;
}

.footer-link:hover {
  color: var(--accent-blue);
}

/* Leaderboard & Podium Slots */
.podium-skeleton,
.podium-slot {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
}

.col-student {
  flex: 1;
}

.col-status {
  text-align: right;
}

.user-bar-right {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-left: auto;
}

/* Smooth Focus Rings */
button:focus-visible,
a:focus-visible,
input:focus-visible,
select:focus-visible,
textarea:focus-visible {
  outline: 2px solid var(--accent-blue, #3b82f6);
  outline-offset: 2px;
}

/* Icon Utilities & Hub Badges */
.hub-icon-badge.hub-icon-list {
  background: rgba(139, 92, 246, 0.12);
  color: #8b5cf6;
}

.hub-icon-badge.hub-icon-check {
  background: rgba(16, 185, 129, 0.12);
  color: #10b981;
}

.icon-expand-fs,
.icon-compress-fs {
  transition: transform 0.15s ease;
}

.audio-icon-play,
.audio-icon-pause {
  display: inline-flex;
  align-items: center;
  justify-content: center;
}

/* ============================================================================
   SIGNATURE MONOCHROME BLACK/WHITE BUTTON SUITE & THEME TOGGLES
   ============================================================================ */

/* Base Button Primitives */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 20px;
  font-size: 0.88rem;
  font-weight: 600;
  border-radius: var(--radius-md, 12px);
  cursor: pointer;
  border: 1px solid transparent;
  user-select: none;
  -webkit-user-select: none;
  text-decoration: none;
  transition: all 0.18s cubic-bezier(0.16, 1, 0.3, 1);
}

.btn:active {
  transform: scale(0.97);
}

/* Primary Button: Solid Black/White High-Contrast CTA */
.btn-primary {
  background: #ffffff;
  color: #09090b;
  border-color: rgba(255, 255, 255, 0.9);
  box-shadow: 0 4px 18px rgba(255, 255, 255, 0.14), 0 2px 6px rgba(0, 0, 0, 0.4);
}

[data-theme="dark"] .btn-primary,
:root:not([data-theme="light"]) .btn-primary {
  background: #ffffff;
  color: #09090b;
  border-color: rgba(255, 255, 255, 0.9);
  box-shadow: 0 4px 18px rgba(255, 255, 255, 0.14), 0 2px 6px rgba(0, 0, 0, 0.4);
}

[data-theme="dark"] .btn-primary:hover,
:root:not([data-theme="light"]) .btn-primary:hover {
  background: #f4f4f5;
  color: #000000;
  transform: translateY(-1px);
  box-shadow: 0 6px 24px rgba(255, 255, 255, 0.24);
}

[data-theme="light"] .btn-primary {
  background: #09090b;
  color: #ffffff;
  border-color: #09090b;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.2);
}

[data-theme="light"] .btn-primary:hover {
  background: #18181b;
  color: #ffffff;
  transform: translateY(-1px);
  box-shadow: 0 6px 22px rgba(0, 0, 0, 0.28);
}

/* Secondary Button: Elevated Clean Glass Surface */
.btn-secondary {
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.12);
  color: #e4e4e7;
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
}

[data-theme="dark"] .btn-secondary,
:root:not([data-theme="light"]) .btn-secondary {
  background: rgba(255, 255, 255, 0.05);
  border-color: rgba(255, 255, 255, 0.12);
  color: #e4e4e7;
}

[data-theme="dark"] .btn-secondary:hover,
:root:not([data-theme="light"]) .btn-secondary:hover {
  background: rgba(255, 255, 255, 0.1);
  border-color: rgba(255, 255, 255, 0.25);
  color: #ffffff;
  transform: translateY(-1px);
}

[data-theme="light"] .btn-secondary {
  background: #ffffff;
  border-color: rgba(0, 0, 0, 0.12);
  color: #18181b;
  box-shadow: 0 1px 4px rgba(0, 0, 0, 0.04);
}

[data-theme="light"] .btn-secondary:hover {
  background: #f8fafc;
  border-color: rgba(0, 0, 0, 0.22);
  color: #000000;
  transform: translateY(-1px);
  box-shadow: 0 3px 10px rgba(0, 0, 0, 0.06);
}

/* Danger Button: High-Contrast Crimson */
.btn-danger {
  background: linear-gradient(135deg, #ef4444 0%, #dc2626 100%);
  color: #ffffff !important;
  border-color: rgba(239, 68, 68, 0.7);
  box-shadow: 0 4px 16px rgba(239, 68, 68, 0.35);
}

.btn-danger:hover {
  background: linear-gradient(135deg, #f87171 0%, #ef4444 100%);
  transform: translateY(-1px);
  box-shadow: 0 6px 22px rgba(239, 68, 68, 0.5);
}

/* Sizing Modifiers */
.btn-xs {
  padding: 5px 10px;
  font-size: 0.76rem;
  border-radius: var(--radius-sm, 6px);
}

.btn-sm {
  padding: 7px 14px;
  font-size: 0.82rem;
  border-radius: var(--radius-sm, 6px);
}

.btn-full {
  width: 100%;
}

/* Sun / Moon Theme Toggle Icon Visibility */
[data-theme="dark"] #themeToggleBtn .icon-sun,
:root:not([data-theme="light"]) #themeToggleBtn .icon-sun {
  display: block;
}

[data-theme="dark"] #themeToggleBtn .icon-moon,
:root:not([data-theme="light"]) #themeToggleBtn .icon-moon {
  display: none;
}

[data-theme="light"] #themeToggleBtn .icon-sun {
  display: none;
}

[data-theme="light"] #themeToggleBtn .icon-moon {
  display: block;
}

/* ============================================================================
   AUDIO ENGINE BADGE CONTROLS
   ============================================================================ */
.audio-engine-badge {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.02em;
  padding: 2px 8px;
  border-radius: var(--radius-pill);
  text-transform: uppercase;
  user-select: none;
  background: rgba(255, 255, 255, 0.08);
  color: var(--text-muted);
  border: 1px solid var(--border-subtle);
  transition: all 0.25s ease;
}

.audio-engine-badge.engine-youtube {
  background: rgba(255, 0, 0, 0.12);
  color: #ff4e4e;
  border-color: rgba(255, 0, 0, 0.35);
  box-shadow: 0 0 8px rgba(255, 0, 0, 0.15);
}

.audio-engine-badge.engine-webaudio {
  background: rgba(16, 185, 129, 0.15);
  color: #10b981;
  border-color: rgba(16, 185, 129, 0.35);
}

.audio-engine-badge.engine-offline {
  background: rgba(59, 130, 246, 0.15);
  color: #60a5fa;
  border-color: rgba(59, 130, 246, 0.35);
}

/* Dedicated Audio Music Preview Card (Music Format with Cover Thumbnail, No Video) */
.custom-music-preview-card {
  margin-top: 14px;
  padding: 12px;
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  gap: 12px;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.08);
  transition: all var(--transition-fast);
}

.custom-music-preview-card:hover {
  border-color: var(--border-focus);
}

.music-preview-cover-wrap {
  position: relative;
  width: 68px;
  height: 68px;
  border-radius: 12px;
  overflow: hidden;
  flex-shrink: 0;
  background: #11141d;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.25);
}

.music-preview-thumb {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.3s ease;
}

.custom-music-preview-card:hover .music-preview-thumb {
  transform: scale(1.05);
}

.music-preview-audio-icon {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(0, 0, 0, 0.35);
  backdrop-filter: blur(1px);
  color: #ffffff;
  pointer-events: none;
}

.music-preview-audio-icon svg {
  width: 22px;
  height: 22px;
  filter: drop-shadow(0 2px 4px rgba(0, 0, 0, 0.5));
}

.music-preview-meta {
  display: flex;
  flex-direction: column;
  gap: 3px;
  min-width: 0;
  flex: 1;
}

.music-preview-format-tag {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  font-size: 0.68rem;
  font-weight: 700;
  color: #10b981;
  text-transform: uppercase;
  letter-spacing: 0.03em;
}

.music-preview-title {
  font-size: 0.88rem;
  font-weight: 700;
  color: var(--text-primary);
  margin: 0;
  line-height: 1.3;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.music-preview-channel {
  font-size: 0.74rem;
  color: var(--text-muted);
}

/* Quick Countdown Duration Presets Row */
.countdown-presets-row {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  flex-wrap: wrap;
  margin: 6px auto 14px;
  max-width: 360px;
  z-index: 10;
  position: relative;
}

.cd-preset-chip {
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-pill);
  color: var(--text-secondary);
  font-size: 0.78rem;
  font-weight: 600;
  padding: 4px 11px;
  cursor: pointer;
  transition: all var(--transition-fast);
  backdrop-filter: blur(8px);
}

.cd-preset-chip:hover {
  background: rgba(255, 255, 255, 0.12);
  color: var(--text-primary);
  border-color: rgba(255, 255, 255, 0.25);
  transform: translateY(-1px);
}

.cd-preset-chip.active {
  background: var(--accent-blue);
  color: #ffffff;
  border-color: var(--accent-blue);
  box-shadow: 0 2px 10px rgba(59, 130, 246, 0.4);
}

.cd-preset-chip.btn-custom-time-gear {
  padding: 4px 8px;
  font-size: 0.85rem;
}

#countdownPresetsRow.locked-active .cd-preset-chip:not(.active) {
  opacity: 0.45;
  cursor: not-allowed;
}

#countdownPresetsRow.locked-active .cd-preset-chip.active {
  pointer-events: none;
}