/* ============================================
   240 Library - Book Cover Browser
   ============================================ */

:root {
  --bg-primary: #0d0d0d;
  --bg-secondary: #1a1a1a;
  --text-primary: #f0ebe3;
  --text-secondary: #8a8578;
  --text-muted: #555555;
  --accent: #c9a962;
  --accent-glow: rgba(201, 169, 98, 0.25);

  /* Cover dimensions - book proportions (2:3 ratio) */
  --cover-height: min(80vh, 550px);
  --cover-width: calc(var(--cover-height) * 0.6667);
  --cover-gap: calc(var(--cover-width) * 0.12);

  /* 3D perspective */
  --perspective: 2000px;
  --focus-range: calc(var(--cover-width) * 2);

  /* Smooth transitions */
  --transition-fast: 100ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-medium: 200ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 400ms cubic-bezier(0.4, 0, 0.2, 1);
}

*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html, body {
  height: 100%;
  overflow: hidden;
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  background: var(--bg-primary);
  color: var(--text-primary);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

.header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  padding: 24px 32px;
  background: linear-gradient(to bottom, var(--bg-primary) 0%, transparent 100%);
  pointer-events: none;
  text-align: center;
}

.header-title {
  font-family: 'Cormorant Garamond', serif;
  font-size: clamp(1.5rem, 4vw, 2.5rem);
  font-weight: 500;
  letter-spacing: 0.15em;
  color: var(--text-primary);
  text-transform: uppercase;
}

.header-link {
  display: inline-block;
  margin-top: 8px;
  font-size: 0.75rem;
  letter-spacing: 0.1em;
  color: var(--text-secondary);
  text-decoration: none;
  pointer-events: auto;
  transition: color var(--transition-fast);
}

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

.coverflow {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  display: flex;
  align-items: center;
  background: var(--bg-primary);
  background-image:
    radial-gradient(ellipse at center, transparent 0%, var(--bg-primary) 70%),
    linear-gradient(to right, var(--bg-primary) 0%, transparent 15%, transparent 85%, var(--bg-primary) 100%);
}

.cover-rail {
  display: flex;
  align-items: center;
  gap: var(--cover-gap);
  width: 100%;
  height: 100vh;
  padding: 0 calc(50vw - var(--cover-width) / 2);
  overflow-x: auto;
  overflow-y: hidden;
  -webkit-overflow-scrolling: touch;
  overscroll-behavior-x: contain;
  perspective: var(--perspective);
  perspective-origin: center center;
  scrollbar-width: none;
  -ms-overflow-style: none;
  scroll-padding: 0 calc(50vw - var(--cover-width) / 2);
}

.cover-rail::-webkit-scrollbar {
  display: none;
}

.cover-tile {
  flex-shrink: 0;
  width: var(--cover-width);
  height: var(--cover-height);
  position: relative;
  cursor: pointer;
  overflow: hidden;
  border-radius: 4px;
  transform-style: preserve-3d;
  backface-visibility: hidden;
  contain: layout paint;
  will-change: transform;
  transition: box-shadow var(--transition-medium), filter var(--transition-medium);
  box-shadow:
    0 4px 16px rgba(0, 0, 0, 0.5),
    0 2px 4px rgba(0, 0, 0, 0.4),
    inset 0 0 0 1px rgba(255, 255, 255, 0.05);
  transform: translateZ(0);
}

.cover-tile::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(
    to right,
    rgba(0, 0, 0, 0.15) 0%,
    transparent 3%,
    transparent 97%,
    rgba(0, 0, 0, 0.1) 100%
  );
  pointer-events: none;
}

.cover-tile picture {
  display: contents;
}

.cover-tile img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  display: block;
  user-select: none;
  -webkit-user-drag: none;
  pointer-events: none;
}

.tile-meta {
  position: absolute;
  bottom: -70px;
  left: 50%;
  transform: translateX(-50%);
  text-align: center;
  white-space: nowrap;
  opacity: 0;
  transition: opacity var(--transition-fast);
  pointer-events: none;
}

.tile-title {
  display: block;
  font-family: 'Cormorant Garamond', serif;
  font-size: 1.25rem;
  font-weight: 500;
  letter-spacing: 0.02em;
  color: var(--text-primary);
}

.tile-author {
  display: block;
  font-size: 0.75rem;
  color: var(--text-secondary);
  margin-top: 4px;
  font-style: italic;
}

.cover-tile.focused {
  z-index: 10;
  box-shadow:
    0 16px 64px rgba(0, 0, 0, 0.7),
    0 8px 24px rgba(0, 0, 0, 0.5),
    0 0 80px var(--accent-glow),
    inset 0 0 0 1px rgba(255, 255, 255, 0.1);
  filter: brightness(1.05);
}

.cover-tile.focused .tile-meta {
  opacity: 1;
  transition: opacity var(--transition-medium) 100ms;
}

.footer {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  z-index: 100;
  padding: 24px 32px;
  background: linear-gradient(to top, var(--bg-primary) 0%, transparent 100%);
  pointer-events: none;
}

.footer-info {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
}

.footer-title {
  font-family: 'Cormorant Garamond', serif;
  font-weight: 500;
  font-size: 1.5rem;
  letter-spacing: 0.05em;
  color: var(--accent);
  transition: color 0.4s ease-out;
  max-width: 80vw;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.footer-subtitle {
  font-size: 0.75rem;
  color: var(--text-secondary);
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

/* Detail Overlay */
.detail-overlay {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 1000;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(0, 0, 0, 0.9);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  opacity: 0;
  visibility: hidden;
  transition: opacity var(--transition-slow), visibility var(--transition-slow);
}

.detail-overlay.active {
  opacity: 1;
  visibility: visible;
}

.detail-panel {
  position: relative;
  max-width: 700px;
  width: 90%;
  max-height: 90vh;
  padding: 48px;
  background: var(--bg-secondary);
  border-radius: 8px;
  border: 1px solid rgba(255, 255, 255, 0.08);
  transform: scale(0.95) translateY(20px);
  transition: transform var(--transition-slow);
}

.detail-overlay.active .detail-panel {
  transform: scale(1) translateY(0);
}

.detail-close {
  position: absolute;
  top: 16px;
  right: 16px;
  width: 40px;
  height: 40px;
  background: transparent;
  border: none;
  color: var(--text-secondary);
  font-size: 2rem;
  line-height: 1;
  cursor: pointer;
  transition: color var(--transition-fast);
}

.detail-close:hover {
  color: var(--text-primary);
}

.detail-content {
  display: flex;
  gap: 40px;
  align-items: flex-start;
}

.detail-cover {
  flex-shrink: 0;
  width: 200px;
  height: 300px;
  object-fit: cover;
  border-radius: 4px;
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.5);
}

.detail-info {
  flex: 1;
  padding-top: 8px;
}

.detail-title {
  font-family: 'Cormorant Garamond', serif;
  font-size: 2.25rem;
  font-weight: 500;
  letter-spacing: 0.02em;
  color: var(--text-primary);
  line-height: 1.2;
}

.detail-author {
  font-size: 1.125rem;
  color: var(--accent);
  margin-top: 8px;
  font-style: italic;
}

.detail-meta {
  display: flex;
  gap: 24px;
  margin-top: 32px;
  padding-top: 24px;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.detail-month {
  font-size: 0.875rem;
  color: var(--text-secondary);
}

.detail-category {
  font-size: 0.875rem;
  color: var(--accent);
  text-transform: capitalize;
}

/* Responsive */
@media (max-width: 768px) {
  :root {
    --cover-height: min(75vh, 450px);
    --cover-width: calc(var(--cover-height) * 0.6667);
    --cover-gap: calc(var(--cover-width) * 0.12);
  }
  .header {
    padding: 16px 20px;
  }
  .footer {
    padding: 16px 20px;
  }
  .detail-panel {
    padding: 24px;
  }
  .detail-content {
    flex-direction: column;
    align-items: center;
    text-align: center;
  }
  .detail-cover {
    width: 160px;
    height: 240px;
  }
  .detail-title {
    font-size: 1.75rem;
  }
  .detail-meta {
    justify-content: center;
  }
}

@media (max-width: 480px) {
  :root {
    --cover-height: min(70vh, 380px);
    --cover-width: calc(var(--cover-height) * 0.6667);
    --cover-gap: calc(var(--cover-width) * 0.1);
  }
  .tile-meta {
    bottom: -60px;
  }
  .tile-title {
    font-size: 1rem;
  }
  .detail-cover {
    width: 140px;
    height: 210px;
  }
}

/* Loading states */
.cover-tile img.loading {
  background: linear-gradient(135deg, var(--bg-secondary) 0%, #252525 50%, var(--bg-secondary) 100%);
  background-size: 200% 200%;
  animation: shimmer 1.5s ease-in-out infinite;
}

@keyframes shimmer {
  0% { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}

.cover-tile:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 4px;
}

.detail-close:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

/* Loading Screen */
.loading-screen {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 9999;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-direction: column;
  background: var(--bg-primary);
  transition: opacity 0.6s ease-out, visibility 0.6s ease-out;
}

.loading-screen.hidden {
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
}

.loader {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 24px;
}

.film-reel {
  width: 80px;
  height: 80px;
  border: 4px solid var(--accent);
  border-radius: 50%;
  position: relative;
  animation: spin 2s linear infinite;
}

.film-reel::before {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 20px;
  height: 20px;
  background: var(--accent);
  border-radius: 50%;
}

.reel-hole {
  position: absolute;
  width: 10px;
  height: 10px;
  background: var(--bg-primary);
  border-radius: 50%;
  top: 50%;
  left: 50%;
}

.reel-hole:nth-child(1) { transform: translate(-50%, -50%) rotate(0deg) translateY(-26px); }
.reel-hole:nth-child(2) { transform: translate(-50%, -50%) rotate(45deg) translateY(-26px); }
.reel-hole:nth-child(3) { transform: translate(-50%, -50%) rotate(90deg) translateY(-26px); }
.reel-hole:nth-child(4) { transform: translate(-50%, -50%) rotate(135deg) translateY(-26px); }
.reel-hole:nth-child(5) { transform: translate(-50%, -50%) rotate(180deg) translateY(-26px); }
.reel-hole:nth-child(6) { transform: translate(-50%, -50%) rotate(225deg) translateY(-26px); }
.reel-hole:nth-child(7) { transform: translate(-50%, -50%) rotate(270deg) translateY(-26px); }
.reel-hole:nth-child(8) { transform: translate(-50%, -50%) rotate(315deg) translateY(-26px); }

@keyframes spin {
  from { transform: rotate(0deg); }
  to { transform: rotate(360deg); }
}

.loader-text {
  font-family: 'Cormorant Garamond', serif;
  font-size: 1.125rem;
  letter-spacing: 0.1em;
  color: var(--text-secondary);
  animation: pulse 1.5s ease-in-out infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 0.5; }
  50% { opacity: 1; }
}