/* Modern Ebook CSS Theme */
:root {
  --bg-main: #f8fafc;
  --bg-sidebar: #ffffff;
  --bg-card: #ffffff;
  --bg-hover: #f1f5f9;
  --bg-active: #e2e8f0;
  
  --text-main: #0f172a;
  --text-muted: #64748b;
  --text-sidebar-heading: #334155;
  --text-sidebar-item: #475569;
  
  --border-color: #e2e8f0;
  --border-subtle: #f1f5f9;
  
  --primary: #2563eb;
  --primary-hover: #1d4ed8;
  --primary-light: #eff6ff;
  
  --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
  --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
  --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
  
  --radius-sm: 6px;
  --radius-md: 8px;
  --radius-lg: 12px;
  
  --font-content: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-size-base: 16px;
  --sidebar-width: 320px;
}

[data-theme="dark"] {
  --bg-main: #0f172a;
  --bg-sidebar: #1e293b;
  --bg-card: #1e293b;
  --bg-hover: #334155;
  --bg-active: #475569;
  
  --text-main: #f8fafc;
  --text-muted: #94a3b8;
  --text-sidebar-heading: #cbd5e1;
  --text-sidebar-item: #94a3b8;
  
  --border-color: #334155;
  --border-subtle: #1e293b;
  
  --primary: #3b82f6;
  --primary-hover: #60a5fa;
  --primary-light: #1e3a8a;
  
  --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.5);
  --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.5);
  --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.5);
}

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

body {
  font-family: var(--font-content);
  font-size: var(--font-size-base);
  background-color: var(--bg-main);
  color: var(--text-main);
  line-height: 1.6;
  overflow-x: hidden;
  height: 100vh;
}

.app-container {
  display: flex;
  height: 100vh;
  overflow: hidden;
}

/* Sidebar Styling matching image */
.sidebar {
  width: var(--sidebar-width);
  background-color: var(--bg-sidebar);
  border-right: 1px solid var(--border-color);
  display: flex;
  flex-direction: column;
  flex-shrink: 0;
  height: 100%;
  transition: transform 0.3s ease;
  z-index: 50;
}

.sidebar-header {
  padding: 20px 16px 12px 16px;
  border-bottom: 1px solid var(--border-subtle);
}

.brand-title {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--text-main);
  letter-spacing: -0.01em;
  line-height: 1.2;
}

.brand-subtitle {
  font-size: 0.8rem;
  color: var(--text-muted);
  margin-top: 4px;
}

.doc-selector-wrap {
  margin-top: 12px;
}

.doc-selector {
  width: 100%;
  padding: 8px 12px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-color);
  background-color: var(--bg-main);
  color: var(--text-main);
  font-size: 0.85rem;
  font-weight: 500;
  outline: none;
  cursor: pointer;
  transition: border-color 0.2s ease;
}

.doc-selector:focus {
  border-color: var(--primary);
}

.sidebar-search {
  padding: 12px 16px;
}

.search-box {
  position: relative;
  width: 100%;
}

.search-input {
  width: 100%;
  padding: 10px 12px 10px 36px;
  border-radius: 20px;
  border: 1px solid var(--border-color);
  background-color: var(--bg-main);
  color: var(--text-main);
  font-size: 0.85rem;
  outline: none;
  transition: all 0.2s ease;
}

.search-input:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.15);
}

.search-icon {
  position: absolute;
  left: 12px;
  top: 50%;
  transform: translateY(-50%);
  width: 16px;
  height: 16px;
  fill: none;
  stroke: var(--text-muted);
  stroke-width: 2;
}

/* Table of Contents Tree */
.toc-container {
  flex: 1;
  overflow-y: auto;
  padding: 12px 16px;
  scrollbar-width: thin;
  scrollbar-color: var(--border-color) transparent;
}

.toc-group {
  margin-bottom: 16px;
}

.toc-heading {
  font-size: 0.75rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-sidebar-heading);
  margin-top: 14px;
  margin-bottom: 6px;
  padding-left: 8px;
}

.toc-list {
  list-style: none;
}

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

.toc-link {
  display: block;
  padding: 6px 10px 6px 12px;
  font-size: 0.85rem;
  color: var(--text-sidebar-item);
  text-decoration: none;
  border-radius: var(--radius-sm);
  transition: all 0.15s ease;
  line-height: 1.4;
  word-break: break-word;
}

.toc-link:hover {
  background-color: var(--bg-hover);
  color: var(--primary);
}

.toc-link.active {
  background-color: var(--primary-light);
  color: var(--primary);
  font-weight: 600;
}

.toc-link.level-2 {
  padding-left: 20px;
}

.toc-link.level-3 {
  padding-left: 30px;
  font-size: 0.82rem;
}

.toc-link.level-4 {
  padding-left: 40px;
  font-size: 0.8rem;
}

/* Main Content Area */
.main-wrapper {
  flex: 1;
  display: flex;
  flex-direction: column;
  height: 100vh;
  overflow: hidden;
}

.top-navbar {
  height: 56px;
  background-color: var(--bg-sidebar);
  border-bottom: 1px solid var(--border-color);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 24px;
  flex-shrink: 0;
}

.navbar-left {
  display: flex;
  align-items: center;
  gap: 12px;
}

.toggle-sidebar-btn {
  display: none;
  background: none;
  border: none;
  color: var(--text-main);
  cursor: pointer;
  padding: 6px;
  border-radius: var(--radius-sm);
}

.toggle-sidebar-btn:hover {
  background-color: var(--bg-hover);
}

.doc-pills {
  display: flex;
  gap: 6px;
  overflow-x: auto;
  max-width: 600px;
  scrollbar-width: none;
}

.doc-pill {
  padding: 5px 12px;
  border-radius: 16px;
  font-size: 0.78rem;
  font-weight: 500;
  background-color: var(--bg-main);
  color: var(--text-muted);
  border: 1px solid var(--border-color);
  cursor: pointer;
  white-space: nowrap;
  transition: all 0.2s ease;
}

.doc-pill:hover {
  border-color: var(--primary);
  color: var(--primary);
}

.doc-pill.active {
  background-color: var(--primary);
  color: #ffffff;
  border-color: var(--primary);
}

.navbar-right {
  display: flex;
  align-items: center;
  gap: 10px;
}

.btn-icon {
  background: none;
  border: 1px solid var(--border-color);
  color: var(--text-main);
  width: 34px;
  height: 34px;
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all 0.2s ease;
}

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

.btn-icon svg {
  width: 18px;
  height: 18px;
  fill: none;
  stroke: currentColor;
  stroke-width: 2;
}

/* Content Container */
.content-area {
  flex: 1;
  overflow-y: auto;
  padding: 32px 48px;
  scroll-behavior: smooth;
}

.content-inner {
  max-width: 920px;
  margin: 0 auto;
  background-color: var(--bg-card);
  padding: 40px;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--border-color);
}

.doc-header-card {
  margin-bottom: 32px;
  padding-bottom: 24px;
  border-bottom: 2px dashed var(--border-color);
}

.doc-header-badge {
  display: inline-block;
  padding: 4px 10px;
  border-radius: 4px;
  font-size: 0.75rem;
  font-weight: 700;
  text-transform: uppercase;
  background-color: var(--primary-light);
  color: var(--primary);
  margin-bottom: 8px;
}

.doc-header-title {
  font-size: 1.8rem;
  font-weight: 800;
  color: var(--text-main);
  line-height: 1.25;
}

.doc-header-sub {
  font-size: 0.95rem;
  color: var(--text-muted);
  margin-top: 6px;
}

/* HTML Rendered Styling */
.rendered-content {
  color: var(--text-main);
  font-size: 1rem;
  line-height: 1.7;
}

.rendered-content h1 {
  font-size: 1.6rem;
  font-weight: 700;
  margin-top: 36px;
  margin-bottom: 16px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--border-color);
  color: var(--text-main);
}

.rendered-content h2 {
  font-size: 1.35rem;
  font-weight: 700;
  margin-top: 28px;
  margin-bottom: 14px;
  color: var(--text-main);
}

.rendered-content h3 {
  font-size: 1.15rem;
  font-weight: 600;
  margin-top: 22px;
  margin-bottom: 10px;
  color: var(--text-main);
}

.rendered-content h4 {
  font-size: 1rem;
  font-weight: 600;
  margin-top: 18px;
  margin-bottom: 8px;
  color: var(--text-main);
}

.rendered-content p {
  margin-bottom: 14px;
  text-align: justify;
}

.rendered-content ul, .rendered-content ol {
  margin-bottom: 16px;
  padding-left: 24px;
}

.rendered-content li {
  margin-bottom: 6px;
}

.rendered-content strong {
  font-weight: 600;
}

/* Custom Table Styling */
.table-responsive {
  width: 100%;
  overflow-x: auto;
  margin: 20px 0;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-color);
}

.ebook-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9rem;
}

.ebook-table th, .ebook-table td {
  padding: 10px 14px;
  border: 1px solid var(--border-color);
  text-align: left;
}

.ebook-table th {
  background-color: var(--bg-hover);
  font-weight: 600;
  color: var(--text-main);
}

.ebook-table tr:nth-child(even) {
  background-color: var(--bg-main);
}

/* Image Styling */
.ebook-img {
  max-width: 100%;
  height: auto;
  display: block;
  margin: 20px auto;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-color);
  box-shadow: var(--shadow-sm);
  cursor: pointer;
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.ebook-img:hover {
  transform: scale(1.01);
  box-shadow: var(--shadow-md);
}

/* Lightbox Modal */
.lightbox-modal {
  display: none;
  position: fixed;
  inset: 0;
  background-color: rgba(0, 0, 0, 0.85);
  backdrop-filter: blur(4px);
  z-index: 1000;
  align-items: center;
  justify-content: center;
  padding: 24px;
}

.lightbox-modal.active {
  display: flex;
}

.lightbox-content {
  max-width: 92vw;
  max-height: 90vh;
  object-fit: contain;
  border-radius: var(--radius-md);
  box-shadow: 0 20px 25px -5px rgba(0,0,0,0.5);
}

.lightbox-close {
  position: absolute;
  top: 20px;
  right: 24px;
  background: rgba(255,255,255,0.2);
  border: none;
  color: white;
  font-size: 24px;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background 0.2s;
}

.lightbox-close:hover {
  background: rgba(255,255,255,0.4);
}

/* Search Modal Overlay */
.search-modal {
  display: none;
  position: fixed;
  inset: 0;
  background-color: rgba(0, 0, 0, 0.5);
  backdrop-filter: blur(2px);
  z-index: 900;
  padding-top: 80px;
}

.search-modal.active {
  display: block;
}

.search-dialog {
  max-width: 640px;
  margin: 0 auto;
  background-color: var(--bg-card);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  border: 1px solid var(--border-color);
  overflow: hidden;
}

.search-dialog-header {
  padding: 16px;
  border-bottom: 1px solid var(--border-color);
  display: flex;
  align-items: center;
  gap: 12px;
}

.search-dialog-input {
  flex: 1;
  border: none;
  background: none;
  font-size: 1.05rem;
  color: var(--text-main);
  outline: none;
}

.search-results-list {
  max-height: 420px;
  overflow-y: auto;
  padding: 8px 0;
}

.search-result-item {
  padding: 12px 20px;
  border-bottom: 1px solid var(--border-subtle);
  cursor: pointer;
  transition: background 0.15s ease;
}

.search-result-item:hover {
  background-color: var(--bg-hover);
}

.search-result-doc {
  font-size: 0.75rem;
  color: var(--primary);
  font-weight: 700;
  margin-bottom: 2px;
}

.search-result-text {
  font-size: 0.9rem;
  color: var(--text-main);
  line-height: 1.4;
}

.highlight-match {
  background-color: #fef08a;
  color: #854d0e;
  padding: 0 2px;
  border-radius: 2px;
}

[data-theme="dark"] .highlight-match {
  background-color: #854d0e;
  color: #fef08a;
}

/* Floating Back to Top */
.back-to-top {
  position: fixed;
  bottom: 24px;
  right: 24px;
  width: 42px;
  height: 42px;
  border-radius: 50%;
  background-color: var(--primary);
  color: white;
  border: none;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  box-shadow: var(--shadow-md);
  opacity: 0;
  pointer-events: none;
  transition: all 0.3s ease;
  z-index: 100;
}

.back-to-top.visible {
  opacity: 1;
  pointer-events: auto;
}

.back-to-top:hover {
  transform: translateY(-2px);
  background-color: var(--primary-hover);
}

/* Mobile Responsive */
@media (max-width: 900px) {
  .sidebar {
    position: fixed;
    transform: translateX(-100%);
  }

  .sidebar.open {
    transform: translateX(0);
  }

  .toggle-sidebar-btn {
    display: flex;
  }

  .content-area {
    padding: 16px;
  }

  .content-inner {
    padding: 20px;
  }

  .doc-pills {
    max-width: 240px;
  }
}