:root {
  --bg-primary: #0f172a;
  --bg-secondary: #1e293b;
  --bg-tertiary: #334155;
  --text-primary: #f8fafc;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;
  --accent: #38bdf8;
  --accent-hover: #0ea5e9;
  --accent-bg: rgba(56, 189, 248, 0.1);
  --border: #334155;
  --card-bg: #1e293b;
  --highlight-bg: #fde047;
  --highlight-text: #0f172a;
  --sidebar-width: 380px;
  --inspector-width: 340px;
  --header-height: 60px;
  --toolbar-height: 50px;
}

[data-theme="light"] {
  --bg-primary: #f8fafc;
  --bg-secondary: #ffffff;
  --bg-tertiary: #e2e8f0;
  --text-primary: #0f172a;
  --text-secondary: #475569;
  --text-muted: #94a3b8;
  --accent: #0284c7;
  --accent-hover: #0369a1;
  --accent-bg: rgba(2, 132, 199, 0.1);
  --border: #e2e8f0;
  --card-bg: #ffffff;
  --highlight-bg: #fef08a;
  --highlight-text: #0f172a;
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background-color: var(--bg-primary);
  color: var(--text-primary);
  height: 100vh;
  overflow: hidden;
  display: flex;
  flex-direction: column;
}

/* Header */
header {
  height: var(--header-height);
  background-color: var(--bg-secondary);
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 20px;
  gap: 20px;
  z-index: 20;
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  font-weight: 700;
  font-size: 1.1rem;
  letter-spacing: -0.02em;
  white-space: nowrap;
}

.brand-badge {
  background: linear-gradient(135deg, #0284c7, #38bdf8);
  color: white;
  padding: 3px 8px;
  border-radius: 6px;
  font-size: 0.75rem;
  font-weight: 800;
  letter-spacing: 0.05em;
}

.header-search {
  flex: 1;
  max-width: 600px;
  position: relative;
  display: flex;
  align-items: center;
}

.header-search input {
  width: 100%;
  padding: 9px 40px 9px 16px;
  background-color: var(--bg-primary);
  border: 1px solid var(--border);
  border-radius: 8px;
  color: var(--text-primary);
  font-size: 0.9rem;
  outline: none;
  transition: all 0.2s ease;
}

.header-search input:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 2px var(--accent-bg);
}

.search-shortcut {
  position: absolute;
  right: 12px;
  font-size: 0.75rem;
  background-color: var(--bg-tertiary);
  color: var(--text-muted);
  padding: 2px 6px;
  border-radius: 4px;
  pointer-events: none;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 10px;
}

.btn-icon {
  background: transparent;
  border: 1px solid var(--border);
  color: var(--text-secondary);
  padding: 8px;
  border-radius: 8px;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1rem;
  transition: all 0.2s;
}

.btn-icon:hover {
  background-color: var(--bg-tertiary);
  color: var(--text-primary);
}

/* Category Filter Bar */
.category-filter-bar {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 6px 20px;
  background-color: var(--bg-secondary);
  border-bottom: 1px solid var(--border);
  overflow-x: auto;
  font-size: 0.85rem;
}

.cat-pill {
  padding: 4px 12px;
  border-radius: 20px;
  background: var(--bg-primary);
  border: 1px solid var(--border);
  color: var(--text-secondary);
  cursor: pointer;
  white-space: nowrap;
  transition: all 0.2s;
}

.cat-pill:hover, .cat-pill.active {
  background-color: var(--accent);
  color: #fff;
  border-color: var(--accent);
}

/* Main Container */
.main-wrapper {
  display: flex;
  flex: 1;
  overflow: hidden;
  position: relative;
}

/* Sidebar */
.sidebar {
  width: var(--sidebar-width);
  background-color: var(--bg-secondary);
  border-right: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  flex-shrink: 0;
  transition: width 0.25s ease;
}

.sidebar.collapsed {
  width: 0;
  border-right: none;
  overflow: hidden;
}

.sidebar-tabs {
  display: flex;
  border-bottom: 1px solid var(--border);
}

.tab-btn {
  flex: 1;
  padding: 12px;
  background: transparent;
  border: none;
  color: var(--text-secondary);
  font-size: 0.85rem;
  font-weight: 600;
  cursor: pointer;
  border-bottom: 2px solid transparent;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  transition: all 0.2s;
}

.tab-btn.active {
  color: var(--accent);
  border-bottom-color: var(--accent);
  background-color: var(--accent-bg);
}

.sidebar-content {
  flex: 1;
  overflow-y: auto;
  padding: 12px;
}

/* TOC Tree */
.toc-group {
  margin-bottom: 12px;
}

.toc-group-header {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
  padding: 6px 8px;
  font-weight: 700;
}

.manual-item {
  border-radius: 6px;
  margin-bottom: 4px;
  overflow: hidden;
}

.manual-header {
  padding: 8px 10px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  cursor: pointer;
  border-radius: 6px;
  font-size: 0.88rem;
  color: var(--text-primary);
  transition: background 0.15s;
}

.manual-header:hover {
  background-color: var(--bg-tertiary);
}

.manual-header.active {
  background-color: var(--accent-bg);
  color: var(--accent);
  font-weight: 600;
}

.manual-pages-badge {
  font-size: 0.72rem;
  background-color: var(--bg-tertiary);
  padding: 2px 6px;
  border-radius: 10px;
  color: var(--text-muted);
}

.toc-subitems {
  padding-left: 12px;
  display: none;
}

.toc-subitems.open {
  display: block;
}

.toc-entry {
  padding: 6px 8px;
  font-size: 0.82rem;
  color: var(--text-secondary);
  border-left: 2px solid var(--border);
  margin-left: 6px;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 6px;
  transition: all 0.15s;
}

.toc-entry:hover {
  color: var(--accent);
  border-left-color: var(--accent);
  background-color: var(--bg-tertiary);
}

.toc-entry.active {
  color: var(--accent);
  border-left-color: var(--accent);
  font-weight: 600;
  background-color: var(--accent-bg);
}

.toc-page-num {
  font-size: 0.72rem;
  color: var(--text-muted);
  flex-shrink: 0;
}

/* Sidebar Search Box */
.sidebar-search-box {
  display: flex;
  align-items: center;
  gap: 8px;
  background-color: var(--bg-primary);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 8px 12px;
  margin-bottom: 12px;
  transition: all 0.2s;
}

.sidebar-search-box:focus-within {
  border-color: var(--accent);
  box-shadow: 0 0 0 2px var(--accent-bg);
}

.sidebar-search-box input {
  flex: 1;
  background: transparent;
  border: none;
  color: var(--text-primary);
  font-size: 16px;
  outline: none;
  min-width: 0;
}

.sidebar-search-box input::placeholder {
  color: var(--text-muted);
  font-size: 0.85rem;
}

.mobile-search-btn {
  display: none;
}

.desktop-only {
  display: inline-flex;
}

/* Search Results */
.search-summary {
  font-size: 0.8rem;
  color: var(--text-muted);
  padding: 6px 4px 12px;
}

.result-card {
  background-color: var(--bg-primary);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 12px;
  margin-bottom: 10px;
  cursor: pointer;
  transition: all 0.15s;
}

.result-card:hover {
  border-color: var(--accent);
  transform: translateY(-1px);
}

.result-meta {
  display: flex;
  align-items: center;
  gap: 6px;
  margin-bottom: 6px;
  font-size: 0.75rem;
}

.doc-tag {
  background-color: var(--bg-tertiary);
  color: var(--accent);
  padding: 2px 6px;
  border-radius: 4px;
  font-weight: 600;
}

.page-tag {
  background-color: var(--bg-tertiary);
  color: var(--text-secondary);
  padding: 2px 6px;
  border-radius: 4px;
}

.result-title {
  font-size: 0.88rem;
  font-weight: 600;
  margin-bottom: 6px;
  color: var(--text-primary);
}

.result-snippet {
  font-size: 0.8rem;
  color: var(--text-secondary);
  line-height: 1.4;
}

.result-snippet mark {
  background-color: var(--highlight-bg);
  color: var(--highlight-text);
  padding: 0 2px;
  border-radius: 2px;
  font-weight: 600;
}

/* Main Viewer Area */
.viewer-wrapper {
  flex: 1;
  display: flex;
  flex-direction: column;
  overflow: hidden;
  background-color: var(--bg-primary);
}

/* Toolbar */
.viewer-toolbar {
  height: var(--toolbar-height);
  background-color: var(--bg-secondary);
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 16px;
  gap: 12px;
  z-index: 10;
}

.toolbar-left, .toolbar-center, .toolbar-right {
  display: flex;
  align-items: center;
  gap: 8px;
}

.doc-info-badge {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--text-primary);
  max-width: 280px;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.page-controls {
  display: flex;
  align-items: center;
  gap: 4px;
  background-color: var(--bg-primary);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 2px 6px;
}

.page-controls input {
  width: 44px;
  text-align: center;
  background: transparent;
  border: none;
  color: var(--text-primary);
  font-size: 0.85rem;
  outline: none;
}

.page-total {
  font-size: 0.82rem;
  color: var(--text-muted);
}

.tool-btn {
  background: var(--bg-primary);
  border: 1px solid var(--border);
  color: var(--text-secondary);
  padding: 6px 10px;
  border-radius: 6px;
  font-size: 0.82rem;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 4px;
  transition: all 0.15s;
}

.tool-btn:hover {
  background-color: var(--bg-tertiary);
  color: var(--text-primary);
  border-color: var(--text-muted);
}

.tool-btn.active {
  background-color: var(--accent);
  color: white;
  border-color: var(--accent);
}

/* Document Container */
.doc-viewport {
  flex: 1;
  overflow: auto;
  position: relative;
  display: flex;
  justify-content: center;
  padding: 20px;
}

#pdf-canvas-container {
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
  background: #ffffff;
  position: relative;
  transition: transform 0.2s ease;
}

#pdf-canvas {
  display: block;
}

/* SVG Viewer */
#svg-container {
  display: none;
  background: #ffffff;
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
  max-width: 100%;
  overflow: auto;
}

#svg-container svg {
  display: block;
  width: 100%;
  height: auto;
}

/* Inspector Drawer */
.inspector-panel {
  width: var(--inspector-width);
  background-color: var(--bg-secondary);
  border-left: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  flex-shrink: 0;
  transition: width 0.25s ease;
}

.inspector-panel.collapsed {
  width: 0;
  border-left: none;
  overflow: hidden;
}

.inspector-header {
  padding: 12px 16px;
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-size: 0.9rem;
  font-weight: 700;
}

.inspector-content {
  flex: 1;
  overflow-y: auto;
  padding: 14px;
}

.legend-section-title {
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
  margin-bottom: 8px;
}

.legend-card {
  background-color: var(--bg-primary);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 10px;
  margin-bottom: 8px;
}

.legend-key {
  display: inline-block;
  background: var(--accent);
  color: white;
  padding: 1px 6px;
  border-radius: 4px;
  font-size: 0.75rem;
  font-weight: 700;
  margin-right: 6px;
}

.legend-desc {
  font-size: 0.82rem;
  color: var(--text-primary);
  line-height: 1.4;
}

.no-legend-notice {
  font-size: 0.85rem;
  color: var(--text-muted);
  font-style: italic;
  text-align: center;
  padding: 30px 10px;
}

/* Loading Spinner */
.spinner {
  border: 3px solid var(--border);
  border-top: 3px solid var(--accent);
  border-radius: 50%;
  width: 24px;
  height: 24px;
  animation: spin 0.8s linear infinite;
  display: inline-block;
}

@keyframes spin {
  0% { transform: rotate(0deg); }
  100% { transform: rotate(360deg); }
}

.loading-overlay {
  position: absolute;
  top: 0; left: 0; right: 0; bottom: 0;
  background: rgba(15, 23, 42, 0.7);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 12px;
  z-index: 50;
  color: white;
  font-size: 0.9rem;
}

/* Mobile Sidebar Header */
.sidebar-header-mobile {
  display: none;
  align-items: center;
  justify-content: space-between;
  padding: 12px 16px;
  border-bottom: 1px solid var(--border);
  font-size: 0.9rem;
  font-weight: 700;
  color: var(--text-primary);
}

/* Mobile Overlay Backdrop */
.mobile-overlay {
  display: none;
  position: fixed;
  top: 0; left: 0; right: 0; bottom: 0;
  background: rgba(0, 0, 0, 0.6);
  backdrop-filter: blur(2px);
  -webkit-backdrop-filter: blur(2px);
  z-index: 998;
  opacity: 0;
  transition: opacity 0.25s ease;
  pointer-events: none;
}

.mobile-overlay.active {
  display: block;
  opacity: 1;
  pointer-events: auto;
}

/* Responsive Mobile Rules (Phones & Small Tablets) */
@media (max-width: 768px) {
  :root {
    --header-height: 52px;
    --toolbar-height: auto;
  }

  header {
    padding: 0 10px;
    gap: 8px;
  }

  .brand span:not(.brand-badge) {
    display: none; /* Keep badge, hide long text */
  }

  .brand-badge {
    font-size: 0.68rem;
    padding: 2px 6px;
  }

  .header-search {
    display: none !important;
  }

  .mobile-search-btn {
    display: flex !important;
  }

  .desktop-only {
    display: none !important;
  }

  .header-actions {
    gap: 6px;
  }

  #toggle-inspector-btn span {
    display: none;
  }
  #toggle-inspector-btn::after {
    content: "📋";
    font-size: 1.1rem;
  }
  #toggle-inspector-btn {
    padding: 6px 10px;
  }

  .category-filter-bar {
    padding: 4px 10px;
    gap: 6px;
  }

  .category-filter-bar span {
    display: none;
  }

  .cat-pill {
    padding: 3px 10px;
    font-size: 0.78rem;
  }

  /* Off-canvas Slide-over Sidebar Drawer */
  .sidebar {
    position: fixed;
    top: 0;
    left: 0;
    bottom: 0;
    width: 86vw;
    max-width: 340px;
    z-index: 1000;
    transform: translateX(-100%);
    transition: transform 0.3s cubic-bezier(0.16, 1, 0.3, 1);
    box-shadow: 4px 0 25px rgba(0, 0, 0, 0.6);
  }

  .sidebar.mobile-open {
    transform: translateX(0) !important;
  }

  .sidebar.collapsed {
    width: 86vw;
    transform: translateX(-100%) !important;
  }

  .sidebar-header-mobile {
    display: flex;
  }

  /* Off-canvas Slide-over Inspector Drawer */
  .inspector-panel {
    position: fixed;
    top: 0;
    right: 0;
    bottom: 0;
    width: 88vw;
    max-width: 360px;
    z-index: 1000;
    transform: translateX(100%);
    transition: transform 0.3s cubic-bezier(0.16, 1, 0.3, 1);
    box-shadow: -4px 0 25px rgba(0, 0, 0, 0.6);
  }

  .inspector-panel.mobile-open {
    transform: translateX(0) !important;
  }

  .inspector-panel.collapsed {
    width: 88vw;
    transform: translateX(100%) !important;
  }

  /* Full-width Viewer Wrapper */
  .viewer-wrapper {
    width: 100vw;
    min-width: 0;
  }

  .viewer-toolbar {
    padding: 6px 8px;
    gap: 6px;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
    flex-wrap: nowrap;
    justify-content: flex-start;
  }

  .toolbar-left {
    flex-shrink: 0;
  }

  .doc-info-badge {
    max-width: 110px;
    font-size: 0.75rem;
  }

  #current-cat-badge {
    display: none !important;
  }

  .toolbar-center {
    flex-shrink: 0;
  }

  .toolbar-right {
    flex-shrink: 0;
  }

  .tool-btn {
    padding: 6px 8px;
    font-size: 0.78rem;
  }

  .doc-viewport {
    padding: 4px 2px;
    align-items: flex-start;
  }

  #pdf-canvas-container {
    max-width: 100%;
  }

  #pdf-canvas {
    max-width: 100% !important;
    height: auto !important;
  }

  #svg-container {
    max-width: 100%;
    width: 100%;
  }
}