/* Book details: predictable navigation, readable hierarchy and mobile layout. */
#detailScreen {
  padding-bottom: calc(var(--bottom-nav-h) + 34px + var(--safe-area-inset-bottom));
}

#detailScreen .detail-header {
  position: sticky;
  top: 0;
  z-index: var(--z-sticky);
  min-height: 54px;
  padding: calc(10px + var(--safe-area-inset-top)) 0 10px;
  background: linear-gradient(to bottom, var(--bg-primary) 76%, rgba(7, 11, 20, .92));
  backdrop-filter: blur(18px);
}

#detailScreen .detail-tabs {
  position: sticky;
  top: calc(54px + var(--safe-area-inset-top));
  z-index: var(--z-sticky);
  justify-content: flex-start;
  gap: 4px;
  padding: 4px;
  scrollbar-width: none;
  box-shadow: 0 8px 20px rgba(0, 0, 0, .2);
  overflow-x: auto;
  scroll-padding-inline: 12px;
  overscroll-behavior-inline: contain;
}
#detailScreen .detail-tabs::-webkit-scrollbar { display: none; }
#detailScreen .detail-tab {
  flex: 0 0 auto;
  min-width: max-content;
  padding: 10px 14px;
  border: 0;
  background: transparent;
  color: var(--text-muted);
  font: inherit;
  font-size: 12px;
  white-space: nowrap;
  overflow: visible;
  text-overflow: clip;
}
#detailScreen .detail-tab:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: -2px;
}
#detailScreen .detail-tab[aria-selected="true"] {
  color: var(--text-primary);
  background: rgba(0, 212, 255, .12);
  box-shadow: inset 0 -2px 0 var(--accent);
}

#detailScreen .detail-content {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: 22px;
}
#detailScreen .detail-hero {
  display: grid;
  grid-template-columns: 112px minmax(0, 1fr);
  align-items: start;
  gap: 16px;
}
#detailScreen .detail-cover {
  position: static;
  top: auto;
  width: 112px;
  height: 158px;
  border-radius: 16px;
  box-shadow: 0 16px 34px rgba(0, 0, 0, .34);
}
#detailScreen .detail-info { min-width: 0; }
#detailScreen .detail-title {
  font-size: clamp(19px, 4.8vw, 25px);
  line-height: 1.18;
  overflow-wrap: anywhere;
}
#detailScreen .detail-author { font-size: 13px; line-height: 1.4; }
#detailScreen .detail-category { max-width: 100%; line-height: 1.45; }
#detailScreen .admin-book-stats { gap: 6px; }
#detailScreen .mylist-status-select {
  width: 100%;
  max-width: 360px;
  min-height: 42px;
  font-size: 13px;
}
#detailScreen .detail-description-section {
  padding: 18px;
  border: 1px solid var(--border);
  border-radius: 16px;
  background: linear-gradient(145deg, rgba(255,255,255,.025), transparent), var(--bg-card);
}
#detailScreen .detail-section-title {
  margin: 0 0 10px;
  color: var(--text-primary);
  font-size: 15px;
}
#detailScreen .detail-desc {
  margin: 0;
  color: var(--text-secondary);
  font-size: 14px;
  line-height: 1.75;
  white-space: pre-line;
}
#detailScreen .detail-actions {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 8px;
}
#detailScreen .btn-detail {
  justify-content: center;
  min-height: 42px;
  padding: 10px 12px;
  font-size: 12px;
  text-align: center;
}
#detailScreen .detail-action-primary {
  grid-column: 1 / -1;
  color: #f8fafc;
  border: 1px solid rgba(103, 232, 249, .42);
  background: linear-gradient(135deg, #087ea4, #4330a8);
  box-shadow: 0 10px 24px rgba(8, 126, 164, .24);
  font-weight: 800;
}
#detailScreen .detail-action-primary:hover { background: linear-gradient(135deg, #076b8b, #35268c); }

#detailScreen .offline-btn-saved {
  width: 42px;
  min-width: 42px;
  padding-inline: 0;
  color: #86efac;
  border-color: rgba(34, 197, 94, .42);
  background: rgba(34, 197, 94, .12);
}
#detailScreen .offline-btn-saved svg { width: 18px; height: 18px; }

@media (max-width: 420px) {
  #detailScreen .detail-hero { grid-template-columns: 94px minmax(0, 1fr); gap: 12px; }
  #detailScreen .detail-cover { width: 94px; height: 134px; }
  #detailScreen .detail-actions { grid-template-columns: minmax(0, 1fr); }
  #detailScreen .detail-action-primary { grid-column: auto; }
  #detailScreen .offline-btn-saved { justify-self: start; }
}

@media (min-width: 768px) {
  #detailScreen .detail-hero { grid-template-columns: 190px minmax(0, 1fr); gap: 28px; }
  #detailScreen .detail-cover { width: 190px; height: 268px; }
  #detailScreen .detail-description-section { padding: 22px 24px; }
  #detailScreen .detail-actions { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  #detailScreen .detail-action-primary { grid-column: auto; }
}

@media (min-width: 1280px) {
  #detailScreen { padding-bottom: 40px; }
  #detailScreen .detail-content { max-width: 980px; margin-inline: auto; }
  #detailScreen .detail-header, #detailScreen .detail-tabs { position: relative; top: auto; }
}

/* Reader and AR UX overrides kept in the component layer. */
.reader-toolbar button,
.reader-search-panel button,
.reader-arrow,
.pomodoro-btn { background: rgba(12, 20, 35, .94); border: 1px solid rgba(103, 232, 249, .24); color: var(--text-primary); box-shadow: 0 4px 14px rgba(0,0,0,.18); }
.reader-toolbar button:hover,
.reader-search-panel button:hover,
.reader-arrow:hover,
.pomodoro-btn:hover { background: rgba(20, 37, 61, .98); border-color: var(--accent); color: var(--accent); }
.reader-focus-mode .reader-toolbar,
.reader-focus-mode .reader-search-panel,
.reader-focus-mode .reader-arrow,
.reader-focus-mode .page-indicator-overlay,
.reader-focus-mode .pomodoro-panel { opacity: 0; pointer-events: none; transition: opacity .18s ease; }
.reader-focus-mode .reader-gesture-zone { cursor: none; }

#arSchemeMenuModal h3 { color: #f8fafc; text-shadow: 0 1px 2px rgba(0,0,0,.55); }
#arSchemeMenuModal h3 + div { color: #cbd5e1; }
.ar-camera-help { position:absolute; left:50%; bottom:72px; z-index:var(--z-modal); transform:translateX(-50%); display:grid; gap:5px; width:min(92vw,430px); padding:12px 14px; border:1px solid rgba(103,232,249,.45); border-radius:14px; background:rgba(5,12,24,.94); color:#f8fafc; box-shadow:0 12px 30px rgba(0,0,0,.35); font-size:12px; line-height:1.45; }
.ar-camera-help strong { color:#67e8f9; font-size:13px; }

/* Foldables report a wide CSS viewport while still being a phone. Keep the
   detail actions compact instead of allowing the primary action to become a
   giant full-width panel. */
@media (max-width: 900px) and (pointer: coarse) {
  #detailScreen .detail-content { gap: 16px; }
  #detailScreen .detail-actions { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 10px; }
  #detailScreen .detail-action-primary { grid-column: 1 / -1; min-height: 54px; font-size: 15px; }
  #detailScreen .btn-detail { min-height: 44px; padding: 10px 12px; font-size: 12px; }
  #detailScreen .offline-btn-save { font-size: 11px; }
  #detailScreen .detail-action-secondary { font-size: 11px; }
}

/* AR menu: turn the flat list into a clear, tactile constellation of cards. */
#arSchemeMenuModal .ar-menu-btn {
  position: relative; overflow: hidden; isolation: isolate;
  min-height: 78px; border: 1px solid rgba(103,232,249,.2);
  background: linear-gradient(135deg, rgba(16,31,53,.96), rgba(20,17,49,.96));
  box-shadow: 0 10px 24px rgba(0,0,0,.18), inset 0 1px rgba(255,255,255,.06);
  transition: transform .18s ease, border-color .18s ease, box-shadow .18s ease;
}
#arSchemeMenuModal .ar-menu-btn::after { content:""; position:absolute; inset:auto -20px -34px auto; width:100px; height:100px; border-radius:50%; background:radial-gradient(circle, rgba(103,232,249,.2), transparent 68%); z-index:-1; }
#arSchemeMenuModal .ar-menu-btn:hover, #arSchemeMenuModal .ar-menu-btn:focus-visible { transform:translateY(-2px); border-color:rgba(103,232,249,.72); box-shadow:0 14px 30px rgba(8,126,164,.22), inset 0 1px rgba(255,255,255,.1); }
#arSchemeMenuModal .ar-menu-icon { border:1px solid rgba(255,255,255,.2); background:linear-gradient(145deg,#0891b2,#6d28d9); color:#fff; box-shadow:0 0 18px rgba(103,232,249,.18); }
#arSchemeMenuModal .ar-menu-title { color:#f8fafc; font-weight:800; }
#arSchemeMenuModal .ar-menu-sub { color:#cbd5e1; }
#arSchemeMenuModal .ar-menu-arrow { color:#67e8f9; font-size:21px; }

@media (prefers-reduced-motion: reduce) {
  #arSchemeMenuModal .ar-menu-btn { transition:none; }
}