/* ═══════════════════════════════════════════
   BOOK DETAIL — APPLE PREMIUM DESIGN SYSTEM
   Fonts: Inter (UI) + Source Serif 4 (Titles)
   ═══════════════════════════════════════════ */

/* ── RESET & BASE ── */
*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  -webkit-overflow-scrolling: touch;
}

body {
  font-family: 'Source Serif 4', 'Inter', -apple-system, BlinkMacSystemFont, 'SF Pro Display', 'Segoe UI', Roboto, sans-serif;
  font-optical-sizing: auto;
  background-color: #0a0a0a;
  color: #f5f5f7;
  overflow-x: hidden;
  min-height: 100vh;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  letter-spacing: -0.01em;
}

.hidden { display: none !important; }

/* Serif font for titles/headings */
.serif { font-family: 'Source Serif 4', Georgia, 'Times New Roman', serif; }

/* ═══════════════════════════════════════════
   NAVIGATION — Frosted Glass
   ═══════════════════════════════════════════ */
.detail-nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  padding: 12px 32px;
  background: rgba(10, 10, 10, 0.65);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
  backdrop-filter: saturate(180%) blur(20px);
  display: flex;
  align-items: center;
  transition: all 0.4s cubic-bezier(0.25, 0.1, 0.25, 1);
  border-bottom: 0.5px solid rgba(255,255,255,0.06);
}

.detail-nav.scrolled {
  background: rgba(10, 10, 10, 0.88);
  border-bottom-color: rgba(255,255,255,0.1);
}

.nav-back {
  display: flex;
  align-items: center;
  gap: 4px;
  text-decoration: none;
  color: #0a84ff;
  transition: opacity 0.25s ease;
}

.nav-back:hover { opacity: 0.7; }

.nav-back .material-symbols-outlined {
  font-size: 28px;
  font-weight: 300;
}

.nav-logo {
  font-family: 'Source Serif 4', Georgia, serif;
  font-size: 17px;
  font-weight: 600;
  color: #f5f5f7;
  letter-spacing: -0.02em;
}

/* ═══════════════════════════════════════════
   HERO VIDEO — Poster → Video Transition
   Prominent video area with hover highlight
   ═══════════════════════════════════════════ */
.hero-section {
  position: relative;
  width: 100%;
  height: 76vh;
  min-height: 440px;
  max-height: 700px;
  background: #000;
  overflow: hidden;
  transition: box-shadow 0.5s cubic-bezier(0.25, 0.1, 0.25, 1);
}

/* Hover highlight — video stands out */
.hero-section:hover {
  box-shadow: 0 0 60px rgba(10, 132, 255, 0.12), 0 0 120px rgba(10, 132, 255, 0.06);
}

.hero-video {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  border: none;
  z-index: 1;
}

/* Poster overlay — fades out after 3s */
.hero-poster {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  z-index: 2;
  transition: opacity 1.5s cubic-bezier(0.25, 0.1, 0.25, 1);
}

.hero-poster.fade-out {
  opacity: 0;
  pointer-events: none;
}

/* Bottom gradient — REMOVED to prevent white overlay and allow video controls */
.hero-gradient-bottom {
  display: none;
}

/* Hero title — positioned at top-left to avoid blocking video controls */
.hero-title-overlay {
  position: absolute;
  top: 70px;
  left: 30px;
  bottom: auto;
  z-index: 4;
  max-width: 50%;
  pointer-events: none;
  transition: opacity 1s cubic-bezier(0.25, 0.1, 0.25, 1);
}

/* After poster fades — title subtly stays visible */
.hero-title-overlay.subtle {
  opacity: 0.35;
}

/* On hover over hero — title fades back more for readability */
.hero-section:hover .hero-title-overlay.subtle {
  opacity: 0.55;
}

.hero-title-text {
  font-family: 'Source Serif 4', Georgia, serif;
  font-size: clamp(20px, 2.8vw, 38px);
  font-weight: 700;
  color: #ffffff;
  text-shadow: 0 2px 20px rgba(0,0,0,0.7), 0 4px 40px rgba(0,0,0,0.5);
  line-height: 1.15;
  letter-spacing: -0.02em;
}

/* Loading spinner */
.hero-section.loading::before {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 36px;
  height: 36px;
  border: 2.5px solid rgba(255,255,255,0.1);
  border-top-color: rgba(255,255,255,0.7);
  border-radius: 50%;
  animation: apple-spin 0.7s linear infinite;
  z-index: 5;
}

@keyframes apple-spin {
  to { transform: translate(-50%, -50%) rotate(360deg); }
}

/* No-video state */
.hero-section.no-video-state {
  height: auto;
  min-height: unset;
  max-height: unset;
  background: linear-gradient(160deg, #1a1a2e 0%, #0f1923 50%, #0a0a0a 100%);
}

/* When no video: hide the duplicate info-section below hero */
.hero-section.no-video-state ~ .info-section {
  display: none;
}

.hero-no-video-content {
  display: flex;
  align-items: center;
  gap: 36px;
  padding: 84px 44px 48px;
}

.hero-no-video-poster {
  width: 180px;
  height: 260px;
  object-fit: cover;
  border-radius: 14px;
  box-shadow: 0 20px 60px rgba(0,0,0,0.4), 0 4px 16px rgba(0,0,0,0.3);
  flex-shrink: 0;
}

.book-cover-fallback {
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, #27344c 0%, #121726 100%);
  color: rgba(223, 235, 255, 0.95);
  font-family: "Inter", "Segoe UI", Arial, sans-serif;
  font-weight: 700;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.hero-no-video-poster-fallback {
  width: 180px;
  height: 260px;
  border-radius: 14px;
  box-shadow: 0 20px 60px rgba(0,0,0,0.4), 0 4px 16px rgba(0,0,0,0.3);
  flex-shrink: 0;
  font-size: 40px;
}

.hero-no-video-info { flex: 1; }

.hero-no-video-info h1 {
  font-family: 'Source Serif 4', Georgia, serif;
  font-size: 34px;
  font-weight: 700;
  color: #f5f5f7;
  margin-bottom: 12px;
  letter-spacing: -0.02em;
}

.hero-no-video-info .info-meta { margin-bottom: 16px; }

.hero-no-video-info .info-description {
  font-size: 15px;
  line-height: 1.6;
  color: rgba(255,255,255,0.7);
}

/* ═══════════════════════════════════════════
   INFO SECTION
   ═══════════════════════════════════════════ */
.info-section {
  padding: 0px 44px 28px;
  background: #0a0a0a;
}

.info-grid {
  display: grid;
  grid-template-columns: 1.5fr 0.5fr;
  gap: 28px;
  max-width: 1080px;
}

.info-left { max-width: 100%; }

.info-meta {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 10px;
  flex-wrap: wrap;
}

.match-badge {
  color: #30d158;
  font-weight: 600;
  font-size: 14px;
  letter-spacing: -0.01em;
}

.rating-badge {
  border: 1px solid rgba(255,255,255,0.25);
  padding: 2px 8px;
  font-size: 11px;
  color: rgba(255,255,255,0.65);
  border-radius: 4px;
  font-weight: 500;
}

.category-badge {
  color: rgba(255,255,255,0.55);
  font-size: 14px;
  font-weight: 400;
}

.premium-access-badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 4px 10px;
  border-radius: 999px;
  background: rgba(245, 158, 11, 0.18);
  border: 1px solid rgba(245, 158, 11, 0.28);
  color: #fbbf24;
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.02em;
}

.premium-access-badge.hidden {
  display: none;
}

/* Description — short, max 3 lines */
.info-description {
  font-family: 'Source Serif 4', Georgia, serif;
  font-size: 15px;
  line-height: 1.65;
  color: rgba(255,255,255,0.7);
  margin-bottom: 20px;
  max-width: 580px;
  display: -webkit-box;
  -webkit-line-clamp: 3;
  line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

/* ═══════════════════════════════════════════
   APPLE PILL BUTTONS — Glassmorphism
   ═══════════════════════════════════════════ */
.format-switcher-shell {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  margin: 0 0 18px;
  padding: 7px;
  border-radius: 999px;
  background:
    linear-gradient(135deg, rgba(255,255,255,0.12), rgba(255,255,255,0.045)),
    rgba(18,18,20,0.78);
  border: 0.5px solid rgba(255,255,255,0.16);
  box-shadow:
    inset 0 1px 0 rgba(255,255,255,0.12),
    0 16px 45px rgba(0,0,0,0.28);
  -webkit-backdrop-filter: blur(22px) saturate(180%);
  backdrop-filter: blur(22px) saturate(180%);
}

.hero-format-switcher-shell {
  margin-top: 2px;
  margin-bottom: 18px;
}

.format-switcher-label {
  padding-left: 12px;
  color: rgba(255,255,255,0.5);
  font-family: 'Inter', -apple-system, sans-serif;
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  white-space: nowrap;
}

.format-switcher {
  position: relative;
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 3px;
  border-radius: 999px;
  background: rgba(0,0,0,0.34);
  border: 0.5px solid rgba(255,255,255,0.08);
}

.format-option {
  position: relative;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 7px;
  min-width: 86px;
  padding: 9px 16px;
  border: none;
  border-radius: 999px;
  background: transparent;
  color: rgba(255,255,255,0.62);
  font-family: 'Inter', -apple-system, sans-serif;
  font-size: 13px;
  font-weight: 700;
  letter-spacing: -0.01em;
  cursor: pointer;
  transition:
    color 0.22s ease,
    background 0.22s ease,
    box-shadow 0.22s ease,
    transform 0.22s ease;
  -webkit-tap-highlight-color: transparent;
}

.format-option .material-symbols-outlined {
  font-size: 18px;
  font-variation-settings: 'FILL' 0, 'wght' 500, 'GRAD' 0, 'opsz' 24;
}

.format-option:hover {
  color: rgba(255,255,255,0.9);
  background: rgba(255,255,255,0.07);
}

.format-option.active {
  color: #111316;
  background: linear-gradient(180deg, rgba(255,255,255,0.98), rgba(232,236,242,0.92));
  box-shadow:
    0 8px 24px rgba(0,0,0,0.28),
    inset 0 1px 0 rgba(255,255,255,0.78);
}

.format-option.active .material-symbols-outlined {
  font-variation-settings: 'FILL' 1, 'wght' 600, 'GRAD' 0, 'opsz' 24;
}

.format-option:active {
  transform: scale(0.97);
}

.btn-apple-primary:disabled {
  cursor: not-allowed;
  opacity: 0.55;
  transform: none;
  box-shadow: none;
}

.action-buttons {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}

.payment-access-note {
  margin-top: 12px;
  font-size: 13px;
  line-height: 1.6;
  color: rgba(255,255,255,0.72);
}

.payment-access-note.hidden {
  display: none;
}

.btn-apple-primary {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 11px 28px;
  background: rgba(255,255,255,0.95);
  color: #1d1d1f;
  border: none;
  border-radius: 980px; /* Apple's pill radius */
  font-family: 'Inter', -apple-system, sans-serif;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s cubic-bezier(0.25, 0.1, 0.25, 1);
  letter-spacing: -0.01em;
  -webkit-tap-highlight-color: transparent;
}

.btn-apple-primary:hover {
  background: rgba(255,255,255,1);
  transform: scale(1.03);
  box-shadow: 0 4px 20px rgba(255,255,255,0.15);
}

.btn-apple-primary:active {
  transform: scale(0.97);
  background: rgba(255,255,255,0.85);
}

.btn-apple-primary .material-symbols-outlined { font-size: 20px; }

.btn-apple-secondary {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 11px 24px;
  background: rgba(255,255,255,0.08);
  color: #f5f5f7;
  border: 1px solid rgba(255,255,255,0.18);
  border-radius: 980px;
  font-family: 'Inter', -apple-system, sans-serif;
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.3s cubic-bezier(0.25, 0.1, 0.25, 1);
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
  letter-spacing: -0.01em;
  -webkit-tap-highlight-color: transparent;
}

.btn-apple-secondary:hover {
  background: rgba(255,255,255,0.14);
  border-color: rgba(255,255,255,0.3);
  transform: scale(1.03);
}

.btn-apple-secondary.my-list-active {
  background: rgba(138,180,248,0.18);
  border-color: rgba(138,180,248,0.42);
  color: #d2e3fc;
}

.btn-apple-secondary:active {
  transform: scale(0.97);
  background: rgba(255,255,255,0.06);
}

.btn-apple-secondary .material-symbols-outlined { font-size: 18px; }

/* Info Right column */
.info-right {
  padding-top: 2px;
}

.info-meta-item {
  margin-bottom: 10px;
  font-size: 13px;
  line-height: 1.5;
}

.meta-label {
  color: rgba(255,255,255,0.4);
  margin-right: 6px;
  font-weight: 500;
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.03em;
  display: block;
  margin-bottom: 2px;
}

.meta-value {
  color: #f5f5f7;
  font-weight: 500;
}

/* ═══════════════════════════════════════════
   MORE DETAILS — Frosted Glass Cards
   ═══════════════════════════════════════════ */
.details-section {
  padding: 24px 44px;
  background: #0a0a0a;
  border-top: 0.5px solid rgba(255,255,255,0.06);
}

.section-title {
  font-family: 'Source Serif 4', Georgia, serif;
  font-size: 22px;
  font-weight: 600;
  color: #f5f5f7;
  margin-bottom: 16px;
  letter-spacing: -0.02em;
}

.details-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
  max-width: 1080px;
}

/* Frosted Glass Card */
.glass-card {
  background: rgba(255,255,255,0.04);
  -webkit-backdrop-filter: blur(16px);
  backdrop-filter: blur(16px);
  border: 0.5px solid rgba(255,255,255,0.08);
  border-radius: 16px;
  padding: 18px 20px;
  transition: all 0.35s cubic-bezier(0.25, 0.1, 0.25, 1);
}

.glass-card:hover {
  background: rgba(255,255,255,0.07);
  border-color: rgba(255,255,255,0.14);
  transform: translateY(-2px);
  box-shadow: 0 8px 30px rgba(0,0,0,0.3);
}

.detail-card h3 {
  font-family: 'Inter', sans-serif;
  font-size: 12px;
  font-weight: 600;
  color: rgba(255,255,255,0.5);
  margin-bottom: 14px;
  padding-bottom: 10px;
  border-bottom: 0.5px solid rgba(255,255,255,0.08);
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.detail-label {
  font-size: 10px;
  color: rgba(255,255,255,0.35);
  margin-bottom: 2px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.detail-value {
  font-size: 13px;
  color: rgba(255,255,255,0.85);
  margin-bottom: 12px;
  line-height: 1.45;
  font-weight: 400;
}

.detail-tags {
  color: #30d158;
  font-style: italic;
  font-family: 'Source Serif 4', serif;
}

/* Summary card — max 4 lines */
.detail-full-desc {
  font-family: 'Source Serif 4', Georgia, serif;
  font-size: 13px;
  line-height: 1.55;
  display: -webkit-box;
  -webkit-line-clamp: 5;
  line-clamp: 5;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

/* ═══════════════════════════════════════════
   RECOMMENDATIONS — Smooth Scroll
   ═══════════════════════════════════════════ */
.recommendations-section {
  padding: 24px 44px 20px;
  background: #0a0a0a;
  border-top: 0.5px solid rgba(255,255,255,0.06);
}

.extra-reco-section {
  padding-top: 26px;
}

.reco-row-wrapper {
  position: relative;
}

.reco-row {
  display: flex;
  gap: 12px;
  overflow-x: auto;
  scroll-behavior: smooth;
  -webkit-overflow-scrolling: touch;
  padding-bottom: 10px;
  scrollbar-width: none;
  scroll-snap-type: x proximity;
}

.reco-row::-webkit-scrollbar { display: none; }

/* Recommendation Cards — Apple rounded */
.reco-card {
  flex: 0 0 170px;
  cursor: pointer;
  color: inherit;
  text-decoration: none;
  border-radius: 12px;
  overflow: hidden;
  position: relative;
  transition: all 0.4s cubic-bezier(0.25, 0.1, 0.25, 1);
  background: #1c1c1e;
  scroll-snap-align: start;
}

.reco-card:hover {
  transform: scale(1.06);
  z-index: 10;
  box-shadow: 0 12px 40px rgba(0,0,0,0.5);
}

.reco-card:active {
  transform: scale(0.98);
}

.reco-card-cover,
.reco-cover-fallback {
  width: 100%;
  height: 245px;
  object-fit: cover;
  display: block;
  transition: all 0.4s cubic-bezier(0.25, 0.1, 0.25, 1);
}

.reco-cover-fallback {
  font-size: 30px;
}

.reco-card:hover .reco-card-cover,
.reco-card:hover .reco-cover-fallback {
  filter: brightness(0.6);
  transform: scale(1.05);
}

.reco-card-info {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  padding: 12px 10px 10px;
  background: linear-gradient(transparent, rgba(0,0,0,0.92));
  opacity: 0;
  transform: translateY(6px);
  transition: all 0.35s cubic-bezier(0.25, 0.1, 0.25, 1);
}

.reco-card:hover .reco-card-info {
  opacity: 1;
  transform: translateY(0);
}

.reco-card-title {
  font-family: 'Source Serif 4', serif;
  font-size: 12px;
  font-weight: 600;
  color: #fff;
  margin-bottom: 3px;
  line-height: 1.3;
}

.reco-card-author {
  font-size: 10px;
  color: rgba(255,255,255,0.6);
}

.reco-card-category {
  display: inline-block;
  font-size: 9px;
  color: #30d158;
  background: rgba(48,209,88,0.1);
  padding: 2px 6px;
  border-radius: 6px;
  margin-top: 3px;
  font-weight: 500;
}

/* Scroll Arrows — Apple style */
.reco-arrow {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  z-index: 10;
  width: 38px;
  height: 38px;
  background: rgba(255,255,255,0.08);
  -webkit-backdrop-filter: blur(12px);
  backdrop-filter: blur(12px);
  border: 0.5px solid rgba(255,255,255,0.12);
  border-radius: 50%;
  color: #f5f5f7;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.3s cubic-bezier(0.25, 0.1, 0.25, 1);
}

.reco-arrow:hover {
  background: rgba(255,255,255,0.16);
  transform: translateY(-50%) scale(1.1);
}

.reco-arrow:active {
  transform: translateY(-50%) scale(0.95);
}

.reco-arrow .material-symbols-outlined { font-size: 22px; }

.reco-arrow-left { left: -6px; }
.reco-arrow-right { right: -6px; }

/* ── FOOTER ── */
.detail-footer {
  padding: 28px 44px;
  background: #000;
  border-top: 0.5px solid rgba(255,255,255,0.04);
  text-align: center;
  color: rgba(255,255,255,0.3);
  font-size: 12px;
  font-weight: 400;
}

/* ═══════════════════════════════════════════
   RESPONSIVE
   ═══════════════════════════════════════════ */
@media (max-width: 900px) {
  .info-grid { grid-template-columns: 1fr; gap: 16px; }
  .details-grid { grid-template-columns: 1fr; }
  .info-section, .details-section, .recommendations-section { padding-left: 20px; padding-right: 20px; }
  .hero-title-overlay { left: 20px; top: 60px; max-width: 75%; }
  .hero-no-video-content { flex-direction: column; text-align: center; padding: 76px 20px 36px; }
  .hero-no-video-poster,
  .hero-no-video-poster-fallback { width: 140px; height: 200px; }
  .hero-no-video-info h1 { font-size: 26px; }
  .detail-nav { padding: 10px 16px; }
}

@media (max-width: 600px) {
  .hero-section { height: 48vh; min-height: 260px; }
  .reco-card { flex: 0 0 140px; }
  .reco-card-cover,
  .reco-cover-fallback { height: 200px; }
  .hero-title-text { font-size: 22px; }
  .section-title { font-size: 18px; }
  .format-switcher-shell {
    display: flex;
    width: 100%;
    max-width: 360px;
    flex-direction: column;
    align-items: stretch;
    gap: 6px;
    border-radius: 22px;
  }
  .format-switcher-label {
    padding: 4px 8px 0;
    text-align: center;
  }
  .format-switcher {
    width: 100%;
  }
  .format-option {
    flex: 1;
    min-width: 0;
  }
  .action-buttons { gap: 8px; }
  .btn-apple-primary { padding: 9px 20px; font-size: 14px; }
  .btn-apple-secondary { padding: 9px 18px; font-size: 13px; }
}

/* ═══════════════════════════════════════════
   APPLE-STYLE ANIMATIONS
   ═══════════════════════════════════════════ */

/* Fade-in on load */
.info-section,
.details-section,
.recommendations-section {
  animation: apple-fade-in 0.6s cubic-bezier(0.25, 0.1, 0.25, 1) both;
}

.details-section { animation-delay: 0.1s; }
.recommendations-section { animation-delay: 0.2s; }

@keyframes apple-fade-in {
  from {
    opacity: 0;
    transform: translateY(16px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}