/* ==========================================================================
   Design System & CSS Variables (Dark Luxury Aesthetics)
   ========================================================================== */
:root {
  --bg-base: #0c0f17;
  --bg-surface: #141923;
  --bg-surface-elevated: #1b2230;
  --bg-surface-glass: rgba(20, 25, 35, 0.75);
  --border-subtle: rgba(255, 255, 255, 0.08);
  --border-focus: rgba(99, 102, 241, 0.5);

  --accent-primary: #6366f1;         /* Indigo 500 */
  --accent-primary-hover: #4f46e5;   /* Indigo 600 */
  --accent-primary-glow: rgba(99, 102, 241, 0.25);
  --accent-emerald: #10b981;         /* Emerald 500 */
  --accent-emerald-glow: rgba(16, 185, 129, 0.25);
  
  --text-main: #f1f5f9;              /* Slate 100 */
  --text-muted: #94a3b8;             /* Slate 400 */
  --text-dim: #64748b;               /* Slate 500 */

  --danger: #ef4444;
  --danger-bg: rgba(239, 68, 68, 0.12);

  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --radius-full: 9999px;

  --font-sans: 'Plus Jakarta Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-mono: 'JetBrains Mono', monospace;

  --player-height: 88px;
  --header-height: 68px;

  --transition-fast: 0.15s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-normal: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

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

body {
  font-family: var(--font-sans);
  background-color: var(--bg-base);
  color: var(--text-main);
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow: hidden;
  height: 100vh;
  width: 100vw;
}

/* Custom Scrollbar */
::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}
::-webkit-scrollbar-track {
  background: rgba(0, 0, 0, 0.15);
}
::-webkit-scrollbar-thumb {
  background: rgba(255, 255, 255, 0.22);
  border-radius: var(--radius-full);
}
::-webkit-scrollbar-thumb:hover {
  background: rgba(255, 255, 255, 0.4);
}

/* Utility classes */
.hidden {
  display: none !important;
}
.hidden-input {
  display: none;
}

/* ==========================================================================
   App Layout
   ========================================================================== */
.app-layout {
  display: flex;
  flex-direction: column;
  height: 100vh;
  position: relative;
  background: radial-gradient(circle at 10% 20%, rgba(99, 102, 241, 0.08) 0%, transparent 40%),
              radial-gradient(circle at 90% 80%, rgba(16, 185, 129, 0.05) 0%, transparent 40%);
}

/* Top Header */
.top-header {
  height: var(--header-height);
  flex-shrink: 0;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid var(--border-subtle);
  background: var(--bg-surface-glass);
  backdrop-filter: blur(16px);
  z-index: 20;
}

.brand {
  display: flex;
  align-items: center;
  gap: 14px;
}
.brand-icon {
  width: 42px;
  height: 42px;
  border-radius: var(--radius-md);
  background: linear-gradient(135deg, var(--accent-primary), #4338ca);
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  box-shadow: 0 4px 14px var(--accent-primary-glow);
}
.brand-text h1 {
  font-size: 1.15rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: #fff;
}
.brand-text h1 span {
  color: var(--accent-primary);
  font-weight: 800;
}
.brand-text .subtitle {
  font-size: 0.76rem;
  color: var(--text-muted);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 12px;
}

.badge-status {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 14px;
  background: rgba(16, 185, 129, 0.12);
  border: 1px solid rgba(16, 185, 129, 0.3);
  border-radius: var(--radius-full);
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--accent-emerald);
}
.pulse-dot {
  width: 8px;
  height: 8px;
  background-color: var(--accent-emerald);
  border-radius: 50%;
  box-shadow: 0 0 10px var(--accent-emerald);
  animation: pulse 2s infinite;
}
@keyframes pulse {
  0% { transform: scale(0.9); opacity: 0.7; }
  50% { transform: scale(1.3); opacity: 1; }
  100% { transform: scale(0.9); opacity: 0.7; }
}

/* ==========================================================================
   Buttons
   ========================================================================== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  font-family: inherit;
  font-weight: 600;
  border: none;
  cursor: pointer;
  border-radius: var(--radius-md);
  transition: all var(--transition-fast);
  text-decoration: none;
}
.btn-primary {
  background: var(--accent-primary);
  color: #fff;
  padding: 8px 16px;
  font-size: 0.88rem;
  box-shadow: 0 2px 10px var(--accent-primary-glow);
}
.btn-primary:hover {
  background: var(--accent-primary-hover);
  transform: translateY(-1px);
}
.btn-primary:active {
  transform: translateY(0);
}

.btn-accent {
  background: linear-gradient(135deg, var(--accent-primary), #4f46e5);
  color: #fff;
  box-shadow: 0 4px 12px var(--accent-primary-glow);
}
.btn-accent:hover {
  filter: brightness(1.1);
  transform: translateY(-1px);
}

.btn-ghost {
  background: transparent;
  color: var(--text-muted);
  border: 1px solid var(--border-subtle);
  padding: 6px 12px;
}
.btn-ghost:hover {
  background: var(--bg-surface-elevated);
  color: var(--text-main);
  border-color: rgba(255, 255, 255, 0.16);
}

.btn-icon {
  width: 38px;
  height: 38px;
  padding: 0;
  border-radius: 50%;
}
.btn-sm {
  padding: 5px 10px;
  font-size: 0.78rem;
  border-radius: var(--radius-sm);
}
.btn-lg {
  padding: 14px 28px;
  font-size: 1rem;
  border-radius: var(--radius-lg);
}

/* ==========================================================================
   Main Content Container
   ========================================================================== */
.main-container {
  flex: 1;
  min-height: 0; /* CRITICAL: Allows inner scrolling containers to function without overflowing window */
  position: relative;
  overflow: hidden;
}

/* Empty State / Drag and Drop Area */
.drop-zone {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 32px;
  background: radial-gradient(circle at center, rgba(30, 41, 59, 0.6) 0%, transparent 70%);
}
.drop-zone.drag-active {
  outline: 3px dashed var(--accent-primary);
  outline-offset: -20px;
  background: rgba(99, 102, 241, 0.08);
}
.drop-content {
  max-width: 620px;
  text-align: center;
  padding: 48px;
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.4);
}
.drop-icon {
  width: 80px;
  height: 80px;
  margin: 0 auto 20px;
  border-radius: 50%;
  background: rgba(99, 102, 241, 0.12);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--accent-primary);
  border: 1px solid rgba(99, 102, 241, 0.25);
}
.drop-content h2 {
  font-size: 1.5rem;
  font-weight: 700;
  margin-bottom: 12px;
  letter-spacing: -0.02em;
}
.drop-instruction {
  color: var(--text-muted);
  font-size: 0.95rem;
  line-height: 1.6;
  margin-bottom: 24px;
}
.drop-instruction code {
  color: var(--accent-emerald);
  background: rgba(16, 185, 129, 0.1);
  padding: 2px 6px;
  border-radius: 4px;
  font-family: var(--font-mono);
  font-size: 0.9em;
}
.default-path-hint {
  background: var(--bg-surface-elevated);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 10px 14px;
  margin-bottom: 28px;
  text-align: left;
  display: flex;
  flex-direction: column;
  gap: 4px;
}
.hint-label {
  font-size: 0.72rem;
  font-weight: 700;
  text-transform: uppercase;
  color: var(--text-dim);
  letter-spacing: 0.05em;
}
.default-path-hint code {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--text-muted);
  word-break: break-all;
}

/* ==========================================================================
   2-Column Workspace Panels
   ========================================================================== */
.content-area {
  display: grid;
  grid-template-columns: 1fr 340px; /* Give primary space to track browser */
  height: 100%;
  gap: 1px;
  background: var(--border-subtle);
}

.panel {
  background: var(--bg-base);
  display: flex;
  flex-direction: column;
  height: 100%;
  overflow: hidden;
}

.panel-header {
  padding: 14px 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid var(--border-subtle);
  background: var(--bg-surface);
}
.panel-title-group {
  display: flex;
  align-items: center;
  gap: 10px;
}
.panel-title-group h2 {
  font-size: 1rem;
  font-weight: 700;
  letter-spacing: -0.01em;
}
.counter-pill {
  padding: 2px 8px;
  background: var(--bg-surface-elevated);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-full);
  font-size: 0.72rem;
  font-family: var(--font-mono);
  color: var(--text-muted);
}

/* Search Box */
.search-box {
  display: flex;
  align-items: center;
  gap: 8px;
  background: var(--bg-surface-elevated);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-full);
  padding: 5px 12px;
  width: 220px;
  transition: all var(--transition-fast);
}
.search-box:focus-within {
  border-color: var(--accent-primary);
  width: 260px;
  box-shadow: 0 0 10px var(--accent-primary-glow);
}
.search-box svg {
  color: var(--text-dim);
}
.search-box input {
  background: transparent;
  border: none;
  outline: none;
  color: var(--text-main);
  font-family: inherit;
  font-size: 0.8rem;
  width: 100%;
}
.search-box input::placeholder {
  color: var(--text-dim);
}

/* Selection Toolbar */
.selection-toolbar {
  padding: 10px 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: rgba(20, 25, 35, 0.4);
  border-bottom: 1px solid var(--border-subtle);
}
.toolbar-left, .toolbar-right {
  display: flex;
  align-items: center;
  gap: 8px;
}
.pill-badge {
  background: rgba(255, 255, 255, 0.25);
  padding: 1px 6px;
  border-radius: var(--radius-full);
  font-size: 0.7rem;
  font-family: var(--font-mono);
  margin-left: 2px;
}

/* Unit Groups Container (Left Panel Scrollable) */
.unit-groups-container {
  flex: 1;
  overflow-y: auto;
  padding: 16px 20px 48px;
  display: flex;
  flex-direction: column;
  gap: 14px;
}

/* Unit Group Accordion / Card */
.unit-group-card {
  flex-shrink: 0; /* CRITICAL: Prevent flexbox from collapsing card height when expanded */
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  overflow: hidden;
  transition: border-color var(--transition-fast);
}
.unit-group-card:hover {
  border-color: rgba(255, 255, 255, 0.14);
}
.unit-group-header {
  padding: 12px 18px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: var(--bg-surface-elevated);
  cursor: pointer;
  user-select: none;
  border-bottom: 1px solid transparent;
}
.unit-group-card.expanded .unit-group-header {
  border-bottom-color: var(--border-subtle);
}
.unit-header-title {
  display: flex;
  align-items: center;
  gap: 12px;
}
.unit-title-text {
  font-weight: 700;
  font-size: 0.94rem;
  color: #fff;
}
.unit-count-text {
  font-size: 0.76rem;
  color: var(--text-dim);
}
.unit-header-actions {
  display: flex;
  align-items: center;
  gap: 10px;
}
.unit-toggle-chevron {
  transition: transform var(--transition-fast);
  color: var(--text-muted);
}
.unit-group-card.expanded .unit-toggle-chevron {
  transform: rotate(180deg);
}

/* Track Items List (Grid layout to fit all tracks on screen) */
.track-items-list {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 8px;
  padding: 12px 14px;
}
.unit-group-card:not(.expanded) .track-items-list {
  display: none;
}

.track-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 8px 12px;
  background: rgba(255, 255, 255, 0.02);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  transition: all var(--transition-fast);
  cursor: pointer;
  min-width: 0;
}
.track-row:hover {
  background-color: rgba(255, 255, 255, 0.06);
  border-color: rgba(255, 255, 255, 0.16);
  transform: translateY(-1px);
}
.track-row.selected {
  background-color: rgba(99, 102, 241, 0.12);
  border-color: rgba(99, 102, 241, 0.45);
}
.track-row.is-current {
  background-color: rgba(16, 185, 129, 0.14);
  border-color: var(--accent-emerald);
  box-shadow: 0 0 10px var(--accent-emerald-glow);
}

.track-row-left {
  display: flex;
  align-items: center;
  gap: 10px;
  flex: 1;
  min-width: 0;
}
.track-checkbox {
  appearance: none;
  width: 17px;
  height: 17px;
  border: 1.5px solid var(--text-dim);
  border-radius: 4px;
  background: transparent;
  cursor: pointer;
  position: relative;
  transition: all var(--transition-fast);
  flex-shrink: 0;
}
.track-checkbox:checked {
  background: var(--accent-primary);
  border-color: var(--accent-primary);
}
.track-checkbox:checked::after {
  content: '';
  position: absolute;
  top: 2px;
  left: 5px;
  width: 4px;
  height: 8px;
  border: solid #fff;
  border-width: 0 2px 2px 0;
  transform: rotate(45deg);
}
.track-num-badge {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--text-dim);
  width: 20px;
  flex-shrink: 0;
}
.track-name-text {
  font-size: 0.85rem;
  font-weight: 500;
  color: var(--text-main);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.track-row.is-current .track-name-text {
  color: var(--accent-emerald);
  font-weight: 700;
}

.track-row-actions {
  display: flex;
  align-items: center;
  gap: 4px;
  flex-shrink: 0;
  margin-left: 6px;
}
.row-play-btn {
  background: transparent;
  border: none;
  width: 26px;
  height: 26px;
  border-radius: 50%;
  color: var(--text-muted);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all var(--transition-fast);
}
.row-play-btn:hover {
  background: var(--accent-primary);
  color: #fff;
  transform: scale(1.1);
}

/* ==========================================================================
   Right Panel: Play Queue
   ========================================================================== */
.queue-panel {
  border-left: 1px solid var(--border-subtle);
}
.queue-mode-bar {
  padding: 10px 20px;
  background: rgba(20, 25, 35, 0.4);
  border-bottom: 1px solid var(--border-subtle);
  font-size: 0.78rem;
  color: var(--text-muted);
}
.queue-list-container {
  flex: 1;
  overflow-y: auto;
  padding: 12px 16px 48px;
  display: flex;
  flex-direction: column;
  gap: 6px;
}
.empty-queue-message {
  text-align: center;
  padding: 48px 24px;
  color: var(--text-dim);
  font-size: 0.85rem;
  line-height: 1.6;
}

.queue-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px 14px;
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  transition: all var(--transition-fast);
}
.queue-item:hover {
  border-color: rgba(255, 255, 255, 0.16);
  background: var(--bg-surface-elevated);
}
.queue-item.active {
  border-color: var(--accent-emerald);
  background: rgba(16, 185, 129, 0.08);
}
.queue-item-left {
  display: flex;
  align-items: center;
  gap: 10px;
  flex: 1;
  min-width: 0;
}
.queue-order-badge {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: var(--bg-surface-elevated);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-dim);
  flex-shrink: 0;
}
.queue-item.active .queue-order-badge {
  background: var(--accent-emerald);
  color: #000;
  font-weight: 700;
}
.queue-item-title {
  font-size: 0.84rem;
  font-weight: 500;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.queue-item.active .queue-item-title {
  color: var(--accent-emerald);
  font-weight: 700;
}

.queue-item-right {
  display: flex;
  align-items: center;
  gap: 6px;
  flex-shrink: 0;
}
.queue-action-btn {
  background: transparent;
  border: none;
  color: var(--text-dim);
  width: 24px;
  height: 24px;
  border-radius: 4px;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: color var(--transition-fast);
}
.queue-action-btn:hover {
  color: var(--danger);
  background: var(--danger-bg);
}

/* ==========================================================================
   Bottom Audio Player Dock (Fixed Bar)
   ========================================================================== */
.player-dock {
  position: relative;
  flex-shrink: 0;
  height: var(--player-height);
  background: rgba(15, 19, 29, 0.98);
  backdrop-filter: blur(20px);
  border-top: 1px solid var(--border-subtle);
  padding: 0 24px;
  z-index: 30;
  box-shadow: 0 -10px 30px rgba(0, 0, 0, 0.5);
}

.player-grid {
  display: grid;
  grid-template-columns: 280px 1fr 280px;
  align-items: center;
  height: 100%;
  gap: 20px;
}

/* 1. Track Info Section */
.player-track-info {
  display: flex;
  align-items: center;
  gap: 14px;
  min-width: 0;
}
.track-artwork {
  width: 48px;
  height: 48px;
  border-radius: var(--radius-md);
  background: var(--bg-surface-elevated);
  border: 1px solid var(--border-subtle);
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  overflow: hidden;
  flex-shrink: 0;
  color: var(--text-dim);
}
.track-artwork.playing {
  background: linear-gradient(135deg, rgba(99, 102, 241, 0.2), rgba(16, 185, 129, 0.2));
  border-color: rgba(16, 185, 129, 0.4);
}
.artwork-waves {
  display: none;
  align-items: flex-end;
  gap: 3px;
  height: 20px;
}
.track-artwork.playing .artwork-waves {
  display: flex;
}
.track-artwork.playing #artDefaultIcon {
  display: none;
}
.artwork-waves span {
  width: 3px;
  background: var(--accent-emerald);
  border-radius: 2px;
  animation: soundWave 1.2s ease-in-out infinite;
}
.artwork-waves span:nth-child(1) { height: 8px; animation-delay: 0.1s; }
.artwork-waves span:nth-child(2) { height: 18px; animation-delay: 0.3s; }
.artwork-waves span:nth-child(3) { height: 12px; animation-delay: 0.2s; }
.artwork-waves span:nth-child(4) { height: 15px; animation-delay: 0.4s; }

@keyframes soundWave {
  0%, 100% { transform: scaleY(0.4); }
  50% { transform: scaleY(1); }
}

.track-meta {
  min-width: 0;
  display: flex;
  flex-direction: column;
}
.track-title {
  font-size: 0.92rem;
  font-weight: 700;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  color: #fff;
}
.track-subtitle {
  font-size: 0.74rem;
  color: var(--text-dim);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

/* 2. Controls & Seekbar Center Section */
.player-center {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 6px;
  max-width: 600px;
  margin: 0 auto;
  width: 100%;
}

.player-controls {
  display: flex;
  align-items: center;
  gap: 16px;
}

.ctrl-btn {
  background: transparent;
  border: none;
  color: var(--text-muted);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  transition: all var(--transition-fast);
  position: relative;
}
.ctrl-btn:hover {
  color: #fff;
  transform: scale(1.08);
}
.ctrl-btn:active {
  transform: scale(0.96);
}

.play-main-btn {
  width: 44px;
  height: 44px;
  background: #fff;
  color: #0c0f17;
  box-shadow: 0 4px 16px rgba(255, 255, 255, 0.25);
}
.play-main-btn:hover {
  background: #f8fafc;
  color: #000;
  transform: scale(1.06);
}

.skip-btn {
  flex-direction: column;
  gap: 0px;
}
.skip-label {
  font-size: 0.62rem;
  font-family: var(--font-mono);
  font-weight: 700;
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -46%);
}

.repeat-tag {
  position: absolute;
  bottom: -4px;
  right: -6px;
  font-size: 0.58rem;
  font-family: var(--font-mono);
  font-weight: 700;
  background: var(--bg-surface-elevated);
  padding: 1px 4px;
  border-radius: 4px;
  border: 1px solid var(--border-subtle);
  color: var(--text-dim);
}
.ctrl-btn.repeat-active {
  color: var(--accent-emerald);
}
.ctrl-btn.repeat-active .repeat-tag {
  background: rgba(16, 185, 129, 0.15);
  border-color: var(--accent-emerald);
  color: var(--accent-emerald);
}

/* Timeline & Seekbar */
.player-timeline {
  display: flex;
  align-items: center;
  gap: 10px;
  width: 100%;
}
.time-label {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--text-dim);
  width: 36px;
  text-align: center;
}

.progress-bar-container {
  flex: 1;
  position: relative;
  height: 5px;
  background: rgba(255, 255, 255, 0.12);
  border-radius: var(--radius-full);
  cursor: pointer;
  overflow: visible;
  transition: height var(--transition-fast);
}
.progress-bar-container:hover {
  height: 8px;
}

.progress-buffered {
  position: absolute;
  top: 0;
  left: 0;
  height: 100%;
  background: rgba(255, 255, 255, 0.18);
  border-radius: var(--radius-full);
  pointer-events: none;
  width: 0%;
}
.progress-fill {
  position: absolute;
  top: 0;
  left: 0;
  height: 100%;
  background: linear-gradient(90deg, var(--accent-primary), var(--accent-emerald));
  border-radius: var(--radius-full);
  pointer-events: none;
  width: 0%;
  transition: width 0.05s linear;
}

.seek-slider {
  position: absolute;
  top: 50%;
  left: 0;
  transform: translateY(-50%);
  width: 100%;
  height: 100%;
  opacity: 0;
  cursor: pointer;
  margin: 0;
}

/* 3. Extra Controls: Speed & Volume */
.player-extra {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 16px;
}

.speed-control-wrapper {
  position: relative;
}
.speed-btn {
  background: var(--bg-surface-elevated);
  border: 1px solid var(--border-subtle);
  color: var(--text-main);
  padding: 4px 10px;
  border-radius: var(--radius-sm);
  font-family: var(--font-mono);
  font-size: 0.76rem;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition-fast);
}
.speed-btn:hover {
  border-color: var(--accent-primary);
  color: #fff;
}
.speed-menu {
  position: absolute;
  bottom: calc(100% + 12px);
  right: 0;
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 6px;
  display: flex;
  flex-direction: column;
  gap: 2px;
  box-shadow: 0 10px 25px rgba(0, 0, 0, 0.4);
  z-index: 50;
  min-width: 140px;
}
.speed-menu button {
  background: transparent;
  border: none;
  color: var(--text-muted);
  padding: 6px 12px;
  border-radius: var(--radius-sm);
  font-family: var(--font-mono);
  font-size: 0.76rem;
  text-align: left;
  cursor: pointer;
  transition: all var(--transition-fast);
}
.speed-menu button:hover {
  background: var(--bg-surface-elevated);
  color: #fff;
}
.speed-menu button.active {
  background: rgba(99, 102, 241, 0.15);
  color: var(--accent-primary);
  font-weight: 700;
}

.volume-container {
  display: flex;
  align-items: center;
  gap: 8px;
}
.volume-slider {
  appearance: none;
  width: 80px;
  height: 4px;
  background: rgba(255, 255, 255, 0.15);
  border-radius: var(--radius-full);
  outline: none;
  cursor: pointer;
}
.volume-slider::-webkit-slider-thumb {
  appearance: none;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: #fff;
  cursor: pointer;
  box-shadow: 0 0 6px rgba(0, 0, 0, 0.4);
}

/* ==========================================================================
   Modal Dialog
   ========================================================================== */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.7);
  backdrop-filter: blur(8px);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 100;
  padding: 20px;
}
.modal-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  max-width: 540px;
  width: 100%;
  box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.6);
  overflow: hidden;
}
.modal-header {
  padding: 18px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid var(--border-subtle);
}
.modal-header h3 {
  font-size: 1.1rem;
  font-weight: 700;
}
.close-btn {
  background: transparent;
  border: none;
  font-size: 1.5rem;
  line-height: 1;
  color: var(--text-dim);
  cursor: pointer;
}
.close-btn:hover {
  color: #fff;
}
.modal-body {
  padding: 24px;
  max-height: 70vh;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  gap: 20px;
  font-size: 0.88rem;
  color: var(--text-muted);
}
.modal-body h4 {
  font-size: 0.94rem;
  color: #fff;
  margin-bottom: 8px;
}
.modal-body ol {
  padding-left: 20px;
  display: flex;
  flex-direction: column;
  gap: 6px;
}
.shortcut-list {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px;
  background: var(--bg-surface-elevated);
  padding: 12px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-subtle);
}
.shortcut-row {
  display: flex;
  align-items: center;
  gap: 10px;
}
kbd {
  background: var(--bg-base);
  border: 1px solid var(--border-subtle);
  border-radius: 4px;
  padding: 2px 7px;
  font-family: var(--font-mono);
  font-size: 0.74rem;
  color: var(--accent-emerald);
  box-shadow: 0 2px 0 rgba(0, 0, 0, 0.4);
}

/* ==========================================================================
   Responsive Adaptations
   ========================================================================== */
@media (max-width: 900px) {
  .content-area {
    grid-template-columns: 1fr;
    grid-template-rows: 1fr 1fr;
  }
  .player-grid {
    grid-template-columns: 1fr auto;
  }
  .player-track-info {
    display: none;
  }
}