/* ==========================================================================
   外刊在线试读平台 - 现代沉浸式阅读器样式 (Reader CSS)
   ========================================================================== */

@import url('https://fonts.googleapis.com/css2?family=Cinzel:wght@600;700;800&family=Inter:wght@300;400;500;600;700&family=Noto+Sans+SC:wght@300;400;500;600;700&family=Noto+Serif+SC:ital,wght@0,300;0,400;0,600;0,700;1,400&display=swap');

:root {
  /* Default Light Theme */
  --bg-primary: #f8fafc;
  --bg-surface: #ffffff;
  --bg-elevated: #ffffff;
  --bg-reader: #ffffff;
  --text-primary: #0f172a;
  --text-secondary: #475569;
  --text-muted: #94a3b8;
  --border-color: #e2e8f0;
  --accent-color: #4f46e5;
  --accent-hover: #4338ca;
  --accent-light: #eef2ff;
  --header-bg: rgba(255, 255, 255, 0.92);
  --drawer-bg: rgba(255, 255, 255, 0.98);
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
}

/* Sepia (Eye-Care / Warm Parchment) */
[data-theme="sepia"] {
  --bg-primary: #f5eedb;
  --bg-surface: #ede3cb;
  --bg-elevated: #faf4e6;
  --bg-reader: #fcf8ee;
  --text-primary: #4a3828;
  --text-secondary: #6e5843;
  --text-muted: #9c846b;
  --border-color: #ded3b8;
  --accent-color: #925828;
  --accent-hover: #78441b;
  --accent-light: #f3e5d0;
  --header-bg: rgba(245, 238, 219, 0.95);
  --drawer-bg: rgba(250, 244, 230, 0.98);
}

/* Dark (Night / OLED) */
[data-theme="dark"] {
  --bg-primary: #090d16;
  --bg-surface: #111827;
  --bg-elevated: #1e293b;
  --bg-reader: #0f172a;
  --text-primary: #f1f5f9;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;
  --border-color: #1e293b;
  --accent-color: #6366f1;
  --accent-hover: #818cf8;
  --accent-light: rgba(99, 102, 241, 0.15);
  --header-bg: rgba(17, 24, 39, 0.92);
  --drawer-bg: rgba(17, 24, 39, 0.98);
}

::selection {
  background-color: #c7d2fe;
  color: #1e1b4b;
}

[data-theme="sepia"] ::selection {
  background-color: #e2cca8;
  color: #3b2a1a;
}

[data-theme="dark"] ::selection {
  background-color: #4338ca;
  color: #ffffff;
}

* {
  box-sizing: border-box;
  -webkit-tap-highlight-color: transparent;
}

body {
  margin: 0;
  padding: 0;
  background-color: var(--bg-primary);
  color: var(--text-primary);
  font-family: 'Inter', 'Noto Sans SC', -apple-system, BlinkMacSystemFont, sans-serif;
  overflow: hidden;
  height: 100vh;
  width: 100vw;
  user-select: none;
  transition: background-color 0.25s ease, color 0.25s ease;
}

/* Glassmorphism Header */
.reader-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: 60px;
  background: var(--header-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-color);
  z-index: 40;
  transition: transform 0.3s ease, opacity 0.3s ease;
}

.reader-header.hidden-bar {
  transform: translateY(-100%);
  opacity: 0;
}

/* Reader Main Viewport */
.reader-viewport {
  position: absolute;
  top: 60px;
  bottom: 44px;
  left: 0;
  right: 0;
  background: var(--bg-reader);
  transition: background-color 0.3s ease, top 0.3s ease, bottom 0.3s ease;
  overflow: hidden;
}

.reader-viewport.fullscreen-mode {
  top: 0;
  bottom: 0;
}

/* Foliate View Custom Component Container */
foliate-view {
  display: block;
  width: 100%;
  height: 100%;
  background: var(--bg-reader);
}

/* Page Navigation Hotspots */
.nav-hotspot {
  position: absolute;
  top: 0;
  bottom: 0;
  width: 15%;
  z-index: 20;
  cursor: pointer;
  display: flex;
  align-items: center;
  opacity: 0;
  transition: opacity 0.25s ease;
}

.nav-hotspot:hover {
  opacity: 1;
}

.nav-hotspot-prev {
  left: 0;
  justify-content: flex-start;
  padding-left: 1.25rem;
  background: linear-gradient(to right, rgba(0, 0, 0, 0.05), transparent);
}

.nav-hotspot-next {
  right: 0;
  justify-content: flex-end;
  padding-right: 1.25rem;
  background: linear-gradient(to left, rgba(0, 0, 0, 0.05), transparent);
}

.nav-btn-icon {
  width: 44px;
  height: 44px;
  border-radius: 9999px;
  background: var(--bg-surface);
  color: var(--text-primary);
  border: 1px solid var(--border-color);
  box-shadow: var(--shadow-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  transition: transform 0.2s ease, background-color 0.2s ease;
}

.nav-btn-icon:hover {
  transform: scale(1.1);
  background: var(--accent-light);
  color: var(--accent-color);
}

/* Bottom Progress Status Bar */
.reader-footer {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  height: 44px;
  background: var(--header-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-top: 1px solid var(--border-color);
  z-index: 40;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 1.5rem;
  font-size: 0.8125rem;
  color: var(--text-secondary);
  transition: transform 0.3s ease, opacity 0.3s ease;
}

.reader-footer.hidden-bar {
  transform: translateY(100%);
  opacity: 0;
}

/* Edition Selector Pills (EN / ZH / Bilingual) */
.edition-pill-group {
  position: absolute;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%);
  display: inline-flex;
  background: var(--bg-surface);
  padding: 3px;
  border-radius: 9999px;
  border: 1px solid var(--border-color);
  box-shadow: var(--shadow-sm);
  z-index: 20;
  white-space: nowrap;
}

.edition-pill-btn {
  padding: 5px 14px;
  border-radius: 9999px;
  font-size: 0.8125rem;
  font-weight: 600;
  color: var(--text-secondary);
  background: transparent;
  border: none;
  cursor: pointer;
  transition: all 0.2s ease;
}

.edition-pill-btn:hover {
  color: var(--text-primary);
}

.edition-pill-btn.active {
  background: var(--accent-color);
  color: #ffffff;
  box-shadow: var(--shadow-sm);
}

/* Drawers (TOC & Books Switcher) */
.drawer-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.45);
  backdrop-filter: blur(4px);
  z-index: 50;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.3s ease;
}

.drawer-backdrop.open {
  opacity: 1;
  pointer-events: auto;
}

.drawer-panel {
  position: fixed;
  top: 0;
  bottom: 0;
  width: 360px;
  max-width: 88vw;
  background: var(--drawer-bg);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-right: 1px solid var(--border-color);
  box-shadow: var(--shadow-xl);
  z-index: 60;
  transform: translateX(-100%);
  transition: transform 0.35s cubic-bezier(0.16, 1, 0.3, 1);
  display: flex;
  flex-direction: column;
}

.drawer-panel.right-drawer {
  left: auto;
  right: 0;
  border-right: none;
  border-left: 1px solid var(--border-color);
  transform: translateX(100%);
}

.drawer-panel.open {
  transform: translateX(0);
}

/* TOC Tree Styles (Supporting Calibre Multi-level & Python Flat) */
.toc-list {
  list-style: none;
  margin: 0;
  padding: 0.5rem 0.75rem;
  overflow-y: auto;
  flex: 1;
}

.toc-item {
  margin-bottom: 2px;
}

.toc-link {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 8px 12px;
  border-radius: 8px;
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 0.875rem;
  line-height: 1.4;
  transition: all 0.15s ease;
  cursor: pointer;
}

.toc-link:hover {
  background: var(--accent-light);
  color: var(--accent-color);
}

.toc-link.active {
  background: var(--accent-light);
  color: var(--accent-color);
  font-weight: 700;
}

/* Section Header for Calibre 2nd-level TOC */
.toc-section-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px 12px;
  margin-top: 6px;
  border-radius: 8px;
  font-weight: 700;
  font-size: 0.875rem;
  color: var(--text-primary);
  background: var(--bg-surface);
  border: 1px solid var(--border-color);
  cursor: pointer;
  transition: background-color 0.15s ease;
}

.toc-section-header:hover {
  background: var(--accent-light);
  color: var(--accent-color);
}

.toc-sublist {
  list-style: none;
  margin: 0;
  padding-left: 1.25rem;
  border-left: 2px solid var(--border-color);
  margin-left: 1rem;
  margin-top: 4px;
  margin-bottom: 6px;
}

.toc-sublist.collapsed {
  display: none;
}

/* Settings Modal & Quick Checkout Modal */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.6);
  backdrop-filter: blur(6px);
  z-index: 70;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 1rem;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.25s ease;
}

.modal-overlay.open {
  opacity: 1;
  pointer-events: auto;
}

.modal-box {
  background: var(--bg-surface);
  color: var(--text-primary);
  border: 1px solid var(--border-color);
  border-radius: 24px;
  box-shadow: var(--shadow-xl);
  max-width: 520px;
  width: 100%;
  max-height: 90vh;
  overflow-y: auto;
  transform: scale(0.95) translateY(10px);
  transition: transform 0.3s cubic-bezier(0.16, 1, 0.3, 1);
}

.modal-overlay.open .modal-box {
  transform: scale(1) translateY(0);
}

/* Floating Sticky Unlock CTA Pill */
.floating-unlock-cta {
  position: fixed;
  bottom: 64px;
  right: 20px;
  z-index: 35;
  background: linear-gradient(135deg, #4f46e5 0%, #7c3aed 100%);
  color: #ffffff;
  font-weight: 700;
  font-size: 0.875rem;
  padding: 10px 18px;
  border-radius: 9999px;
  box-shadow: 0 10px 25px -5px rgba(79, 70, 229, 0.45);
  display: flex;
  align-items: center;
  gap: 8px;
  cursor: pointer;
  transition: transform 0.25s ease, box-shadow 0.25s ease;
  border: 1px solid rgba(255, 255, 255, 0.2);
}

.floating-unlock-cta:hover {
  transform: translateY(-3px) scale(1.03);
  box-shadow: 0 15px 30px -5px rgba(79, 70, 229, 0.6);
}

/* Custom Scrollbars */
::-webkit-scrollbar {
  width: 6px;
  height: 6px;
}
::-webkit-scrollbar-track {
  background: transparent;
}
::-webkit-scrollbar-thumb {
  background: var(--border-color);
  border-radius: 9999px;
}
::-webkit-scrollbar-thumb:hover {
  background: var(--text-muted);
}

/* Reader Loading Spinner */
.reader-loader-overlay {
  position: absolute;
  inset: 0;
  background: var(--bg-reader);
  z-index: 30;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 16px;
  transition: opacity 0.3s ease;
}

.reader-loader-overlay.fade-out {
  opacity: 0;
  pointer-events: none;
}

.spinner {
  width: 48px;
  height: 48px;
  border: 4px solid var(--border-color);
  border-top-color: var(--accent-color);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

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

/* ===== Theme-Aware Header/Footer/Drawer Elements ===== */

/* Header interactive buttons */
.reader-header .header-icon-btn {
  color: var(--text-secondary);
  transition: color 0.2s ease, background-color 0.2s ease;
}
.reader-header .header-icon-btn:hover {
  color: var(--accent-color);
  background: var(--accent-light);
}

/* Header back link */
.reader-header .header-back-link {
  color: var(--text-secondary);
  transition: color 0.2s ease, background-color 0.2s ease;
}
.reader-header .header-back-link:hover {
  color: var(--accent-color);
  background: var(--accent-light);
}

/* Header book title */
.reader-header .header-book-title {
  color: var(--text-primary);
}

/* Header book issue badge */
.reader-header .header-issue-badge {
  color: var(--text-muted);
  background: var(--bg-surface);
}

/* Header divider */
.reader-header .header-divider {
  background: var(--border-color);
}

/* TOC button text */
.reader-header .header-toc-btn {
  color: var(--text-secondary);
}
.reader-header .header-toc-btn:hover {
  color: var(--accent-color);
  background: var(--accent-light);
}
.reader-header .header-toc-btn svg {
  color: var(--accent-color);
}

/* Footer progress text */
.reader-footer .footer-progress {
  color: var(--text-primary);
  font-weight: 700;
}

/* Checkout CTA button in header - always visible */
.reader-header .header-checkout-btn {
  background: var(--accent-color);
  color: #ffffff;
}
.reader-header .header-checkout-btn:hover {
  background: var(--accent-hover);
}

/* Drawer header/footer theme-aware */
.drawer-panel .drawer-header {
  border-color: var(--border-color);
}
.drawer-panel .drawer-title {
  color: var(--text-primary);
}
.drawer-panel .drawer-close-btn {
  color: var(--text-muted);
}
.drawer-panel .drawer-close-btn:hover {
  color: var(--text-primary);
  background: var(--accent-light);
}
.drawer-panel .drawer-footer {
  border-color: var(--border-color);
  background: var(--bg-elevated);
}
.drawer-panel .drawer-footer-text {
  color: var(--text-muted);
}

/* Books Drawer Card theme-aware */
.books-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-color);
  transition: all 0.2s ease;
}
.books-card:hover {
  border-color: var(--accent-color);
  box-shadow: var(--shadow-md);
}
.books-card.active {
  background: var(--accent-light);
  border-color: var(--accent-color);
  box-shadow: var(--shadow-sm);
}
.books-card .card-badge {
  background: var(--bg-elevated);
  color: var(--text-secondary);
}
.books-card.active .card-badge {
  background: var(--accent-color);
  color: #ffffff;
}
.books-card .card-title {
  color: var(--text-primary);
}
.books-card .card-desc {
  color: var(--text-muted);
}
.books-card .card-issue {
  color: var(--text-muted);
}

/* TOC Search Input theme-aware */
.toc-search-wrap {
  border-color: var(--border-color);
}
.toc-search-input {
  background: var(--bg-elevated) !important;
  border-color: var(--border-color) !important;
  color: var(--text-primary) !important;
}
.toc-search-input::placeholder {
  color: var(--text-muted) !important;
}

/* Settings Modal theme-aware */
.modal-box .settings-title {
  color: var(--text-primary);
}
.modal-box .settings-label {
  color: var(--text-muted);
}
.modal-box .settings-divider {
  border-color: var(--border-color);
}

/* Settings buttons base style */
.setting-option-btn {
  background: var(--bg-surface);
  color: var(--text-secondary);
  border: 1px solid var(--border-color);
  transition: all 0.2s ease;
}
.setting-option-btn:hover {
  border-color: var(--accent-color);
}

/* Selected state for font family / layout buttons */
.setting-option-btn.selected {
  background: var(--accent-color) !important;
  color: #ffffff !important;
  border-color: var(--accent-color) !important;
}

/* Theme option button selected ring */
.setting-theme-btn.selected {
  outline: 2px solid var(--accent-color);
  outline-offset: 2px;
}

/* Font size adjuster theme */
.font-size-adjuster {
  background: var(--bg-elevated);
  border: 1px solid var(--border-color);
}
.font-size-adjuster .font-size-btn {
  background: var(--bg-surface);
  color: var(--text-primary);
  box-shadow: var(--shadow-sm);
}
.font-size-adjuster .font-size-btn:hover {
  background: var(--accent-light);
}
.font-size-adjuster .font-size-display {
  color: var(--text-primary);
}

/* Mobile Responsiveness Tweaks */
@media (max-width: 640px) {
  .reader-header {
    height: 52px;
    padding: 0 0.5rem;
  }
  .reader-viewport {
    top: 52px;
    bottom: 38px;
  }
  .reader-footer {
    height: 38px;
    padding: 0 1rem;
    font-size: 0.75rem;
  }
  .edition-pill-btn {
    padding: 3px 8px;
    font-size: 0.72rem;
  }
  .nav-hotspot {
    width: 22%;
  }
  .nav-btn-icon {
    display: none; /* Rely on tap/swipe on mobile */
  }
  .floating-unlock-cta {
    bottom: 50px;
    right: 12px;
    padding: 8px 14px;
    font-size: 0.75rem;
  }
}