/* Reader App - Styles
   Modern Glassmorphism, Dark/Light Theme
   No AI watermarks.
*/

/* === CSS Variables / Themes === */
:root,
[data-theme="dark"] {
  --bg: #0a0a0f;
  --bg-secondary: #12121a;
  --bg-card: rgba(255, 255, 255, 0.04);
  --bg-glass: rgba(255, 255, 255, 0.06);
  --bg-glass-hover: rgba(255, 255, 255, 0.10);
  --bg-glass-strong: rgba(255, 255, 255, 0.08);
  --border: rgba(255, 255, 255, 0.08);
  --border-hover: rgba(255, 255, 255, 0.15);
  --text: #e4e4ed;
  --text-secondary: #8888a0;
  --text-muted: #5a5a70;
  --accent: #7c5cfc;
  --accent-hover: #6a4ae8;
  --accent-light: rgba(124, 92, 252, 0.15);
  --accent-glow: rgba(124, 92, 252, 0.3);
  --success: #34d399;
  --warning: #fbbf24;
  --error: #ef4444;
  --scrollbar: rgba(255, 255, 255, 0.08);
  --scrollbar-hover: rgba(255, 255, 255, 0.15);
  --shadow: 0 8px 32px rgba(0, 0, 0, 0.4);
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.3);
  --gradient: linear-gradient(135deg, #7c5cfc, #a855f7);
  --player-bg: rgba(10, 10, 15, 0.92);
}

[data-theme="light"] {
  --bg: #f5f5f7;
  --bg-secondary: #ededf0;
  --bg-card: rgba(255, 255, 255, 0.7);
  --bg-glass: rgba(255, 255, 255, 0.6);
  --bg-glass-hover: rgba(255, 255, 255, 0.85);
  --bg-glass-strong: rgba(0, 0, 0, 0.04);
  --border: rgba(0, 0, 0, 0.08);
  --border-hover: rgba(0, 0, 0, 0.15);
  --text: #1a1a2e;
  --text-secondary: #6b6b80;
  --text-muted: #a0a0b0;
  --accent: #7c5cfc;
  --accent-hover: #6a4ae8;
  --accent-light: rgba(124, 92, 252, 0.10);
  --accent-glow: rgba(124, 92, 252, 0.15);
  --success: #10b981;
  --warning: #f59e0b;
  --error: #ef4444;
  --scrollbar: rgba(0, 0, 0, 0.08);
  --scrollbar-hover: rgba(0, 0, 0, 0.15);
  --shadow: 0 8px 32px rgba(0, 0, 0, 0.08);
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.06);
  --gradient: linear-gradient(135deg, #7c5cfc, #a855f7);
  --player-bg: rgba(245, 245, 247, 0.95);
}

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

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  background: var(--bg);
  color: var(--text);
  min-height: 100vh;
  transition: background 0.3s ease, color 0.3s ease;
  overflow-x: hidden;
}

/* Scrollbar */
::-webkit-scrollbar {
  width: 6px;
  height: 6px;
}
::-webkit-scrollbar-track {
  background: transparent;
}
::-webkit-scrollbar-thumb {
  background: var(--scrollbar);
  border-radius: 3px;
}
::-webkit-scrollbar-thumb:hover {
  background: var(--scrollbar-hover);
}

/* === Layout === */
#app {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

.view {
  display: none;
  flex: 1;
  animation: fadeIn 0.3s ease;
}

.view.active {
  display: flex;
  flex-direction: column;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: translateY(0); }
}

/* === Header === */
.header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 24px;
  background: var(--bg-secondary);
  border-bottom: 1px solid var(--border);
  backdrop-filter: blur(12px);
  position: sticky;
  top: 0;
  z-index: 100;
}

.logo {
  font-size: 1.25rem;
  font-weight: 700;
  letter-spacing: -0.02em;
  background: var(--gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.btn-icon {
  background: none;
  border: 1px solid var(--border);
  color: var(--text-secondary);
  cursor: pointer;
  padding: 8px;
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.2s ease;
  width: 36px;
  height: 36px;
}

.btn-icon:hover {
  background: var(--bg-glass-hover);
  color: var(--text);
  border-color: var(--border-hover);
  transform: translateY(-1px);
}

.btn-icon:active {
  transform: translateY(0);
}

.btn-icon:disabled {
  opacity: 0.35;
  cursor: not-allowed;
  transform: none;
}

/* === Shelf View === */
#shelf-view {
  padding: 0;
}

/* Upload Section */
.upload-section {
  padding: 32px 24px;
  max-width: 600px;
  margin: 0 auto;
  width: 100%;
}

.dropzone {
  background: var(--bg-glass);
  border: 2px dashed var(--border);
  border-radius: 16px;
  padding: 48px 24px;
  text-align: center;
  cursor: pointer;
  transition: all 0.3s ease;
  position: relative;
  overflow: hidden;
}

.dropzone::before {
  content: '';
  position: absolute;
  inset: 0;
  background: var(--accent-light);
  opacity: 0;
  transition: opacity 0.3s ease;
}

.dropzone:hover,
.dropzone.dragover {
  border-color: var(--accent);
  background: var(--accent-light);
  transform: translateY(-2px);
  box-shadow: 0 0 30px var(--accent-glow);
}

.dropzone:hover::before,
.dropzone.dragover::before {
  opacity: 1;
}

.dropzone p {
  position: relative;
  z-index: 1;
  color: var(--text-secondary);
  font-size: 0.95rem;
}

.dropzone i {
  position: relative;
  z-index: 1;
  color: var(--accent);
}

/* Upload Progress */
.upload-progress {
  margin-top: 16px;
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px 16px;
  background: var(--bg-glass);
  border-radius: 12px;
  border: 1px solid var(--border);
}

.progress-bar {
  flex: 1;
  height: 6px;
  background: var(--bg-glass-strong);
  border-radius: 3px;
  overflow: hidden;
}

.progress-fill {
  height: 100%;
  background: var(--gradient);
  border-radius: 3px;
  transition: width 0.3s ease;
}

#progress-text {
  font-size: 0.85rem;
  color: var(--text-secondary);
  min-width: 45px;
  text-align: right;
}

/* Error */
.error {
  color: var(--error);
  font-size: 0.85rem;
  padding: 8px 12px;
  background: rgba(239, 68, 68, 0.1);
  border: 1px solid rgba(239, 68, 68, 0.2);
  border-radius: 8px;
  margin-top: 12px;
}

.hidden {
  display: none !important;
}

/* Bookshelf */
.bookshelf {
  padding: 24px;
  max-width: 1000px;
  margin: 0 auto;
  width: 100%;
}

.book-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: 20px;
}

.empty-shelf {
  grid-column: 1 / -1;
  text-align: center;
  padding: 64px 24px;
  color: var(--text-muted);
}

.empty-shelf p {
  margin-top: 12px;
  font-size: 1rem;
}

/* Book Card */
.book-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 16px;
  overflow: hidden;
  cursor: pointer;
  transition: all 0.3s ease;
  backdrop-filter: blur(8px);
}

.book-card:hover {
  transform: translateY(-6px);
  border-color: var(--accent);
  box-shadow: 0 12px 40px rgba(124, 92, 252, 0.15);
}

.book-cover {
  width: 100%;
  aspect-ratio: 3 / 4;
  background: var(--bg-glass-strong);
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  position: relative;
}

.book-cover-img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.book-cover-placeholder {
  color: var(--text-muted);
  display: flex;
  align-items: center;
  justify-content: center;
  width: 100%;
  height: 100%;
}

.book-info {
  padding: 14px;
}

.book-title {
  font-weight: 600;
  font-size: 0.9rem;
  line-height: 1.3;
  color: var(--text);
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.book-author {
  font-size: 0.8rem;
  color: var(--text-secondary);
  margin-top: 4px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.book-progress {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-top: 10px;
}

.book-progress-bar {
  flex: 1;
  height: 4px;
  background: var(--bg-glass-strong);
  border-radius: 2px;
  overflow: hidden;
}

.book-progress-fill {
  height: 100%;
  background: var(--gradient);
  border-radius: 2px;
  transition: width 0.5s ease;
}

.book-progress-text {
  font-size: 0.75rem;
  color: var(--text-muted);
  min-width: 32px;
  text-align: right;
}

/* === Reader View === */
#reader-view {
  height: 100vh;
  display: none;
  flex-direction: column;
}

#reader-view.active {
  display: flex;
}

/* Reader Topbar */
.reader-topbar {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px 20px;
  background: var(--bg-secondary);
  border-bottom: 1px solid var(--border);
  backdrop-filter: blur(12px);
  position: sticky;
  top: 0;
  z-index: 50;
}

.reader-title {
  flex: 1;
  font-weight: 600;
  font-size: 0.95rem;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.reader-actions {
  display: flex;
  gap: 8px;
}

/* Reader Body */
.reader-body {
  display: flex;
  flex: 1;
  overflow: hidden;
  position: relative;
}

/* TOC Panel */
.toc-panel {
  width: 280px;
  min-width: 280px;
  background: var(--bg-secondary);
  border-right: 1px solid var(--border);
  overflow-y: auto;
  padding: 16px;
  transition: transform 0.3s ease, opacity 0.3s ease;
}

.toc-panel.hidden {
  display: none;
}

.toc-title {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 12px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--border);
}

.toc-list {
  list-style: none;
}

.toc-item {
  padding: 8px 12px;
  border-radius: 8px;
  font-size: 0.85rem;
  color: var(--text-secondary);
  cursor: pointer;
  transition: all 0.15s ease;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.toc-item:hover {
  background: var(--bg-glass);
  color: var(--text);
}

.toc-item.active {
  background: var(--accent-light);
  color: var(--accent);
  font-weight: 500;
}

/* Reader Main */
.reader-main {
  flex: 1;
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

.content-area {
  flex: 1;
  overflow-y: auto;
  padding: 40px 48px;
  max-width: 720px;
  margin: 0 auto;
  width: 100%;
  line-height: 1.8;
  font-size: 1.05rem;
}

.chapter-content p {
  margin-bottom: 1.2em;
  color: var(--text);
}

.chapter-content .chapter-heading {
  font-size: 1.35rem;
  font-weight: 700;
  margin: 1.8em 0 1em;
  color: var(--text);
  line-height: 1.3;
}

.chapter-content .empty-chapter {
  color: var(--text-muted);
  text-align: center;
  padding: 48px;
  font-style: italic;
}

.loading {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 80px 24px;
  color: var(--text-muted);
  font-size: 0.95rem;
}

/* === TTS Player === */
.player {
  background: var(--player-bg);
  border-top: 1px solid var(--border);
  padding: 12px 24px;
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  display: flex;
  align-items: center;
  gap: 20px;
  position: sticky;
  bottom: 0;
  z-index: 40;
}

.player-controls {
  display: flex;
  align-items: center;
  gap: 6px;
}

.play-group {
  display: flex;
  align-items: center;
  gap: 6px;
  margin-right: 4px;
}

.play-label {
  font-size: 0.75rem;
  font-weight: 500;
  color: var(--text-secondary);
  white-space: nowrap;
}

.btn-play:disabled {
  opacity: 0.5;
  background: var(--bg-glass-strong);
  border: 1px dashed var(--text-muted);
  box-shadow: none;
}

.btn-play:disabled + .play-label {
  opacity: 0.4;
}

@media (max-width: 480px) {
  .play-label {
    display: none;
  }
}

.btn-play {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--gradient);
  color: white;
  border: none;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all 0.2s ease;
}

.btn-play:hover:not(:disabled) {
  transform: scale(1.08);
  box-shadow: 0 0 20px var(--accent-glow);
}

.btn-play:active:not(:disabled) {
  transform: scale(0.95);
}

.btn-play:disabled {
  opacity: 0.35;
  cursor: not-allowed;
  transform: none;
  box-shadow: none;
}

.player-extras {
  display: flex;
  align-items: center;
  gap: 20px;
  flex: 1;
}

.speed-group,
.voice-group {
  display: flex;
  align-items: center;
  gap: 8px;
}

.speed-group label,
.voice-group label {
  font-size: 0.75rem;
  color: var(--text-muted);
  font-weight: 500;
}

#speed-range {
  -webkit-appearance: none;
  appearance: none;
  width: 80px;
  height: 4px;
  background: var(--bg-glass-strong);
  border-radius: 2px;
  outline: none;
  cursor: pointer;
}

#speed-range::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--accent);
  cursor: pointer;
  transition: transform 0.15s ease;
}

#speed-range::-webkit-slider-thumb:hover {
  transform: scale(1.2);
}

#speed-range::-moz-range-thumb {
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: var(--accent);
  border: none;
  cursor: pointer;
}

#speed-label {
  font-size: 0.8rem;
  color: var(--text-secondary);
  font-weight: 600;
  min-width: 32px;
}

#voice-select {
  background: var(--bg-glass);
  border: 1px solid var(--border);
  color: var(--text);
  padding: 4px 8px;
  border-radius: 8px;
  font-size: 0.8rem;
  cursor: pointer;
  outline: none;
  font-family: inherit;
  transition: border-color 0.2s ease;
}

#voice-select:focus {
  border-color: var(--accent);
}

.player-time {
  display: flex;
  align-items: center;
  gap: 4px;
  font-size: 0.8rem;
  font-weight: 500;
  color: var(--text-secondary);
  font-variant-numeric: tabular-nums;
}

/* === Toast === */
.toast {
  position: fixed;
  bottom: 80px;
  left: 50%;
  transform: translateX(-50%) translateY(20px);
  background: var(--bg-secondary);
  color: var(--text);
  border: 1px solid var(--border);
  padding: 10px 20px;
  border-radius: 12px;
  font-size: 0.85rem;
  font-weight: 500;
  z-index: 200;
  opacity: 0;
  transition: all 0.3s ease;
  pointer-events: none;
  backdrop-filter: blur(12px);
  box-shadow: var(--shadow);
}

.toast.show {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

/* === Responsive === */
@media (max-width: 768px) {
  .header {
    padding: 12px 16px;
  }

  .upload-section {
    padding: 20px 16px;
  }

  .dropzone {
    padding: 32px 16px;
  }

  .bookshelf {
    padding: 16px;
  }

  .book-grid {
    grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
    gap: 12px;
  }

  .content-area {
    padding: 24px 20px;
    font-size: 1rem;
    max-width: 100%;
  }

  .reader-topbar {
    padding: 8px 12px;
  }

  .toc-panel {
    position: fixed;
    left: 0;
    top: 56px;
    bottom: 0;
    z-index: 60;
    width: 260px;
    box-shadow: var(--shadow);
  }

  .player {
    padding: 10px 12px;
    flex-wrap: wrap;
    gap: 8px;
  }

  .player-extras {
    gap: 12px;
    flex-wrap: wrap;
  }

  .voice-group {
    display: none;
  }

  #speed-range {
    width: 60px;
  }
}

@media (max-width: 480px) {
  .book-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: 10px;
  }

  .book-info {
    padding: 10px;
  }

  .book-title {
    font-size: 0.82rem;
  }

  .book-author {
    font-size: 0.72rem;
  }

  .player-time {
    font-size: 0.72rem;
  }
}