/* Modern Smart Highlighter Reader - Enhanced UI */

/* CSS Variables for consistent theming */
:root {
  /* Light Theme Colors */
  --primary-color: #6366f1;
  --primary-hover: #4f46e5;
  --secondary-color: #8b5cf6;
  --accent-color: #06b6d4;
  --success-color: #10b981;
  --warning-color: #f59e0b;
  --error-color: #ef4444;
  
  /* Background Colors */
  --bg-primary: #ffffff;
  --bg-secondary: #f8fafc;
  --bg-tertiary: #f1f5f9;
  --bg-card: #ffffff;
  --bg-overlay: rgba(0, 0, 0, 0.1);
  --bg-hover: rgba(99, 102, 241, 0.08);
  
  /* Text Colors */
  --text-primary: #1e293b;
  --text-secondary: #64748b;
  --text-muted: #94a3b8;
  --text-inverse: #ffffff;
  
  /* Border Colors */
  --border-light: #e2e8f0;
  --border-medium: #cbd5e1;
  --border-focus: #6366f1;
  
  /* Shadow Colors */
  --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);
  
  /* Spacing */
  --spacing-xs: 0.25rem;
  --spacing-sm: 0.5rem;
  --spacing-md: 1rem;
  --spacing-lg: 1.5rem;
  --spacing-xl: 2rem;
  --spacing-2xl: 3rem;
  
  /* Border Radius */
  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-2xl: 1.5rem;
  
  /* Transitions */
  --transition-fast: 0.15s ease;
  --transition-normal: 0.3s ease;
  --transition-slow: 0.5s ease;
}

/* Dark Theme Colors */
[data-theme="dark"] {
  --bg-primary: #0f172a;
  --bg-secondary: #1e293b;
  --bg-tertiary: #334155;
  --bg-card: #1e293b;
  --bg-overlay: rgba(0, 0, 0, 0.3);
  --bg-hover: rgba(99, 102, 241, 0.18);
  
  --text-primary: #f1f5f9;
  --text-secondary: #cbd5e1;
  --text-muted: #94a3b8;
  
  --border-light: #334155;
  --border-medium: #475569;
  
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.3);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.3), 0 2px 4px -1px rgba(0, 0, 0, 0.2);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.3), 0 4px 6px -2px rgba(0, 0, 0, 0.2);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.3), 0 10px 10px -5px rgba(0, 0, 0, 0.2);
}

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

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  background: linear-gradient(135deg, var(--bg-primary) 0%, var(--bg-secondary) 100%);
  color: var(--text-primary);
  line-height: 1.6;
  transition: all var(--transition-normal);
  min-height: 100vh;
  overflow-x: hidden;
}

/* Smooth scrolling */
html {
  scroll-behavior: smooth;
}

/* App Container */
.app-container {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  background: var(--bg-primary);
  position: relative;
}

/* Glassmorphism effect for header */
.app-header {
  background: rgba(255, 255, 255, 0.8);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border-light);
  padding: var(--spacing-lg) var(--spacing-xl);
  display: flex;
  justify-content: space-between;
  align-items: center;
  position: sticky;
  top: 0;
  z-index: 100;
  box-shadow: var(--shadow-sm);
}

[data-theme="dark"] .app-header {
  background: rgba(30, 41, 59, 0.8);
  border-bottom: 1px solid var(--border-light);
}

.header-content {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
}

.header-icon {
  font-size: 2rem;
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.header-title {
  font-size: 1.5rem;
  font-weight: 700;
  background: linear-gradient(135deg, var(--text-primary), var(--primary-color));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.header-controls {
  display: flex;
  gap: var(--spacing-md);
  align-items: center;
}

/* Modern Button Styles */
.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--spacing-sm);
  padding: var(--spacing-sm) var(--spacing-lg);
  border: none;
  border-radius: var(--radius-lg);
  font-weight: 600;
  font-size: 0.875rem;
  cursor: pointer;
  transition: all var(--transition-fast);
  text-decoration: none;
  position: relative;
  overflow: hidden;
}

.btn::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
  transition: left var(--transition-normal);
}

.btn:hover::before {
  left: 100%;
}

.btn-primary {
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  color: var(--text-inverse);
  box-shadow: var(--shadow-md);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

.btn-secondary {
  background: var(--bg-card);
  color: var(--text-primary);
  border: 1px solid var(--border-light);
  box-shadow: var(--shadow-sm);
}

.btn-secondary:hover {
  background: var(--bg-secondary);
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

.btn-ghost {
  background: transparent;
  color: var(--text-secondary);
  border: 1px solid transparent;
}

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

/* Main Content Layout */
.book-view {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 360px;
  flex: 1;
  gap: var(--spacing-xl);
  padding: var(--spacing-xl);
  max-width: 1560px;
  margin: 0 auto;
  width: 100%;
  align-items: start;
}

.book-content {
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: var(--spacing-xl);
  overflow-y: auto;
  max-height: calc(100vh - 130px);
}

/* Reading Mode Styles */
body.reading-mode .camera-section {
  display: none;
}

body.reading-mode .book-view {
  grid-template-columns: 1fr;
}

body.reading-mode .book-content {
  max-width: 800px;
  margin: 0 auto;
  width: 100%;
}

/* Modern Card Design */
.card {
  background: var(--bg-card);
  border-radius: var(--radius-xl);
  padding: var(--spacing-xl);
  box-shadow: var(--shadow-md);
  border: 1px solid var(--border-light);
  transition: all var(--transition-normal);
  position: relative;
  overflow: hidden;
}

.card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--primary-color), var(--secondary-color), var(--accent-color));
}

.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-xl);
}

.card-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: var(--spacing-lg);
  flex-wrap: wrap;
  gap: var(--spacing-md);
}

.card-title {
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
}

.card-controls {
  display: flex;
  gap: var(--spacing-sm);
  flex-wrap: wrap;
}

/* Camera Section */
.camera-section {
  text-align: center;
  position: relative;
  background: linear-gradient(135deg, var(--bg-secondary), var(--bg-tertiary));
  border-radius: var(--radius-xl);
  padding: var(--spacing-lg);
  border: 2px solid var(--border-light);
  transition: all var(--transition-normal);
}

.camera-section:hover {
  border-color: var(--primary-color);
  box-shadow: var(--shadow-lg);
}

.camera-section video {
  width: 100%;
  max-width: 640px;
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-lg);
  border: 3px solid var(--border-light);
  transition: all var(--transition-normal);
  background: var(--bg-tertiary);
}

.camera-section video:hover {
  border-color: var(--primary-color);
  transform: scale(1.02);
}

.camera-section canvas {
  display: none;
  width: 100%;
  max-width: 640px;
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow-lg);
}

/* Camera status indicator */
.camera-status {
  position: absolute;
  top: var(--spacing-md);
  right: var(--spacing-md);
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--error-color);
  transition: all var(--transition-normal);
}

.camera-status.active {
  background: var(--success-color);
  box-shadow: 0 0 10px var(--success-color);
}

.camera-status.initializing {
  background: var(--warning-color);
  animation: pulse 1.5s infinite;
}

.camera-status.denied {
  background: var(--error-color);
  box-shadow: 0 0 10px var(--error-color);
}

.camera-status.unknown {
  background: var(--text-muted);
  box-shadow: 0 0 10px var(--text-muted);
}

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

/* Camera loading state */
.camera-section.loading {
  opacity: 0.7;
  pointer-events: none;
}

.camera-section.loading::after {
  content: '🔄 Initializing camera...';
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  background: var(--bg-primary);
  padding: var(--spacing-md);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  z-index: 10;
}

/* Camera permission warning */
.camera-permission-warning {
  background: linear-gradient(135deg, #fef3c7, #fde68a);
  border: 2px solid var(--warning-color);
  border-radius: var(--radius-lg);
  padding: var(--spacing-lg);
  margin: var(--spacing-md) 0;
  text-align: center;
}

[data-theme="dark"] .camera-permission-warning {
  background: linear-gradient(135deg, #1e293b, #334155);
  border-color: var(--warning-color);
}

.camera-permission-warning h4 {
  color: var(--warning-color);
  margin-bottom: var(--spacing-sm);
}

/* Troubleshooting Section */
.troubleshooting-section {
  margin-top: var(--spacing-lg);
  padding: var(--spacing-lg);
  background: linear-gradient(135deg, #dbeafe, #bfdbfe);
  border: 2px solid var(--accent-color);
  border-radius: var(--radius-lg);
  text-align: left;
}

[data-theme="dark"] .troubleshooting-section {
  background: linear-gradient(135deg, #1e293b, #334155);
  border-color: var(--accent-color);
}

.troubleshooting-section h4 {
  color: var(--accent-color);
  margin-bottom: var(--spacing-md);
  text-align: center;
}

.troubleshooting-steps {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-md);
}

.troubleshooting-steps .step {
  background: var(--bg-primary);
  padding: var(--spacing-md);
  border-radius: var(--radius-md);
  border-left: 4px solid var(--accent-color);
}

.troubleshooting-steps .step strong {
  color: var(--accent-color);
  display: block;
  margin-bottom: var(--spacing-xs);
}

.troubleshooting-steps .step p {
  margin: 0;
  color: var(--text-secondary);
  font-size: 0.9rem;
}

.camera-controls {
  display: flex;
  gap: var(--spacing-md);
  justify-content: center;
  margin-top: var(--spacing-lg);
  flex-wrap: wrap;
}

/* Text Display */
.text-display {
  min-height: 200px;
  padding: var(--spacing-lg);
  border: 2px solid var(--border-light);
  border-radius: var(--radius-lg);
  background: var(--bg-secondary);
  font-family: 'Georgia', serif;
  line-height: 1.8;
  font-size: 1rem;
  white-space: pre-wrap;
  overflow-y: auto;
  transition: all var(--transition-normal);
  resize: vertical;
}

.text-display:focus {
  outline: none;
  border-color: var(--primary-color);
  box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.1);
}

/* Highlights Display */
.highlights-display {
  min-height: 150px;
  padding: var(--spacing-lg);
  border: 2px solid var(--border-light);
  border-radius: var(--radius-lg);
  background: linear-gradient(135deg, #fef3c7, #fde68a);
  font-family: 'Georgia', serif;
  line-height: 1.8;
  font-size: 1rem;
  white-space: pre-wrap;
  overflow-y: auto;
  transition: all var(--transition-normal);
}

[data-theme="dark"] .highlights-display {
  background: linear-gradient(135deg, #1e293b, #334155);
  color: var(--text-primary);
}

/* Bookmarks */
.bookmarks-list {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-md);
  max-height: 300px;
  overflow-y: auto;
}

.bookmark-item {
  background: var(--bg-secondary);
  border-radius: var(--radius-lg);
  padding: var(--spacing-lg);
  border-left: 4px solid var(--primary-color);
  transition: all var(--transition-normal);
  position: relative;
}

.bookmark-item:hover {
  transform: translateX(4px);
  box-shadow: var(--shadow-md);
}

.bookmark-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: var(--spacing-sm);
}

.bookmark-time {
  font-size: 0.875rem;
  color: var(--text-muted);
  font-weight: 500;
}

.delete-btn {
  background: var(--error-color);
  color: var(--text-inverse);
  border: none;
  padding: var(--spacing-xs) var(--spacing-sm);
  border-radius: var(--radius-md);
  cursor: pointer;
  font-size: 0.75rem;
  transition: all var(--transition-fast);
}

.delete-btn:hover {
  background: #dc2626;
  transform: scale(1.1);
}

.bookmark-content {
  font-size: 0.875rem;
  line-height: 1.6;
  color: var(--text-secondary);
}

/* Sidebar */
.sidebar {
  background: var(--bg-secondary);
  padding: var(--spacing-xl);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-2xl);
  display: flex;
  flex-direction: column;
  gap: var(--spacing-xl);
  overflow-y: auto;
  max-height: calc(100vh - 130px);
  position: sticky;
  top: 100px;
  box-shadow: var(--shadow-sm);
}

.sidebar-section h4 {
  margin-bottom: var(--spacing-lg);
  color: var(--text-secondary);
  font-size: 0.875rem;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  font-weight: 600;
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
}

/* Sidebar Button Styling */
.sidebar-btn {
  background: var(--bg-secondary);
  color: var(--text-primary);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  padding: var(--spacing-md);
  margin-bottom: var(--spacing-sm);
  cursor: pointer;
  transition: all 0.2s ease;
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  width: 100%;
  text-align: left;
  font-size: 0.9rem;
}

.sidebar-btn:hover {
  background: var(--bg-hover);
  border-color: var(--accent-color);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.sidebar-btn:active {
  transform: translateY(0);
}

.sidebar-btn.loading {
  opacity: 0.7;
  cursor: not-allowed;
  background: var(--accent-color);
  color: white;
}

.sidebar-btn.success {
  background: #10b981;
  color: white;
  border-color: #10b981;
}

.sidebar-btn.error {
  background: #ef4444;
  color: white;
  border-color: #ef4444;
}

.sidebar-icon {
  font-size: 1.2rem;
  min-width: 24px;
}

.sidebar-label {
  font-weight: 500;
}

.sidebar-upload-label {
  background: var(--bg-secondary);
  color: var(--text-primary);
  border: 2px dashed var(--border-light);
  border-radius: var(--radius-lg);
  padding: var(--spacing-md);
  margin-bottom: var(--spacing-sm);
  cursor: pointer;
  transition: all 0.2s ease;
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  width: 100%;
  text-align: left;
  font-size: 0.9rem;
}

.sidebar-upload-label:hover {
  border-color: var(--accent-color);
  background: var(--bg-hover);
}

.sidebar-upload-label.dragover {
  border-color: var(--accent-color);
  background: var(--accent-color);
  color: white;
}

.sidebar-upload-label:hover {
  border-color: var(--primary-color);
  background: rgba(99, 102, 241, 0.05);
  transform: translateY(-2px);
}

/* Progress Bar */
.reading-progress {
  background: var(--bg-card);
  padding: var(--spacing-lg) var(--spacing-xl);
  border-top: 1px solid var(--border-light);
  display: flex;
  align-items: center;
  gap: var(--spacing-lg);
  box-shadow: var(--shadow-sm);
}

.progress-bar {
  flex: 1;
  height: 12px;
  background: var(--bg-tertiary);
  border-radius: var(--radius-2xl);
  overflow: hidden;
  position: relative;
}

.progress-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--primary-color), var(--secondary-color), var(--accent-color));
  width: 0%;
  transition: width var(--transition-slow);
  position: relative;
}

.progress-fill::after {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.3), transparent);
  animation: shimmer 2s infinite;
}

@keyframes shimmer {
  0% { transform: translateX(-100%); }
  100% { transform: translateX(100%); }
}

.progress-text {
  font-size: 0.875rem;
  color: var(--text-secondary);
  font-weight: 500;
  white-space: nowrap;
}

/* Modals */
.modal {
  display: none;
  position: fixed;
  z-index: 1000;
  left: 0;
  top: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.5);
  backdrop-filter: blur(4px);
  -webkit-backdrop-filter: blur(4px);
  animation: fadeIn var(--transition-normal);
}

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

.modal-content {
  background: var(--bg-card);
  margin: 5% auto;
  padding: var(--spacing-2xl);
  border-radius: var(--radius-2xl);
  width: 90%;
  max-width: 600px;
  max-height: 80vh;
  overflow-y: auto;
  box-shadow: var(--shadow-xl);
  border: 1px solid var(--border-light);
  animation: slideUp var(--transition-normal);
}

@keyframes slideUp {
  from { 
    opacity: 0;
    transform: translateY(20px);
  }
  to { 
    opacity: 1;
    transform: translateY(0);
  }
}

.modal h3 {
  margin-bottom: var(--spacing-xl);
  color: var(--text-primary);
  font-size: 1.5rem;
  font-weight: 700;
}

.modal-btn {
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  color: var(--text-inverse);
  border: none;
  padding: var(--spacing-md) var(--spacing-xl);
  border-radius: var(--radius-lg);
  cursor: pointer;
  font-weight: 600;
  margin-top: var(--spacing-lg);
  transition: all var(--transition-fast);
}

.modal-btn:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

/* Quiz and Flashcards */
.quiz-questions,
.flashcards {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-md);
}

.quiz-questions p,
.flashcard {
  background: var(--bg-secondary);
  padding: var(--spacing-lg);
  border-radius: var(--radius-lg);
  border-left: 4px solid var(--primary-color);
  line-height: 1.6;
  transition: all var(--transition-normal);
}

.quiz-questions p:hover,
.flashcard:hover {
  transform: translateX(4px);
  box-shadow: var(--shadow-md);
}

/* Notification System */
.notification {
  position: fixed;
  top: 20px;
  right: 20px;
  z-index: 1000;
  max-width: 300px;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  overflow: hidden;
}

.notification-content {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--spacing-md) var(--spacing-lg);
  color: var(--text-inverse);
}

.notification-message {
  flex: 1;
  margin-right: var(--spacing-sm);
  font-weight: 500;
}

.notification-close {
  background: none;
  border: none;
  color: var(--text-inverse);
  font-size: 1.25rem;
  cursor: pointer;
  padding: 0;
  width: 20px;
  height: 20px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  transition: all var(--transition-fast);
}

.notification-close:hover {
  background: rgba(255, 255, 255, 0.2);
}

/* Loading states */
.loading {
  position: relative;
  overflow: hidden;
}

.loading::after {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.4), transparent);
  animation: loading 1.5s infinite;
}

@keyframes loading {
  0% { left: -100%; }
  100% { left: 100%; }
}

/* Responsive Design */
@media (max-width: 1024px) {
  .book-view {
    grid-template-columns: 1fr;
    padding: var(--spacing-lg);
    gap: var(--spacing-lg);
  }
  
  .sidebar {
    position: static;
    max-height: none;
    padding: var(--spacing-lg);
  }
  
  .book-content {
    max-height: none;
  }
}

@media (max-width: 768px) {
  .app-header {
    padding: var(--spacing-md);
    flex-direction: column;
    gap: var(--spacing-md);
  }
  
  .header-controls {
    width: 100%;
    justify-content: center;
  }
  
  .card-header {
    flex-direction: column;
    align-items: stretch;
  }
  
  .card-controls {
    justify-content: center;
  }
  
  .camera-controls {
    flex-direction: column;
  }
  
  .modal-content {
    margin: 10% auto;
    width: 95%;
    padding: var(--spacing-lg);
  }
  
  .reading-progress {
    flex-direction: column;
    gap: var(--spacing-md);
  }
  
  .notification {
    right: 10px;
    left: 10px;
    max-width: none;
  }
}

/* Accessibility */
@media (prefers-reduced-motion: reduce) {
  * {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

/* Focus styles for accessibility */
button:focus,
input:focus,
textarea:focus,
[contenteditable]:focus {
  outline: 2px solid var(--primary-color);
  outline-offset: 2px;
}

/* Print styles */
@media print {
  .sidebar,
  .app-header,
  .camera-section,
  .reading-progress {
    display: none;
  }
  
  .book-view {
    grid-template-columns: 1fr;
  }
  
  .book-content {
    padding: 0;
  }
  
  .card {
    box-shadow: none;
    border: 1px solid #000;
  }
}

/* Custom scrollbar */
::-webkit-scrollbar {
  width: 8px;
}

::-webkit-scrollbar-track {
  background: var(--bg-secondary);
  border-radius: var(--radius-md);
}

::-webkit-scrollbar-thumb {
  background: var(--border-medium);
  border-radius: var(--radius-md);
}

::-webkit-scrollbar-thumb:hover {
  background: var(--text-muted);
}

/* Utility classes */
.text-center { text-align: center; }
.text-left { text-align: left; }
.text-right { text-align: right; }

.mb-0 { margin-bottom: 0; }
.mb-1 { margin-bottom: var(--spacing-sm); }
.mb-2 { margin-bottom: var(--spacing-md); }
.mb-3 { margin-bottom: var(--spacing-lg); }
.mb-4 { margin-bottom: var(--spacing-xl); }

.mt-0 { margin-top: 0; }
.mt-1 { margin-top: var(--spacing-sm); }
.mt-2 { margin-top: var(--spacing-md); }
.mt-3 { margin-top: var(--spacing-lg); }
.mt-4 { margin-top: var(--spacing-xl); }

.p-0 { padding: 0; }
.p-1 { padding: var(--spacing-sm); }
.p-2 { padding: var(--spacing-md); }
.p-3 { padding: var(--spacing-lg); }
.p-4 { padding: var(--spacing-xl); }

.hidden { display: none; }
.block { display: block; }
.flex { display: flex; }
.grid { display: grid; }

.items-center { align-items: center; }
.justify-center { justify-content: center; }
.justify-between { justify-content: space-between; }

.w-full { width: 100%; }
.h-full { height: 100%; }

/* Mobile-specific camera access button */
.mobile-only {
  display: none;
}

/* Show mobile buttons only on mobile devices */
@media (max-width: 768px) {
  .mobile-only {
    display: inline-block;
  }
}

/* Accent button style */
.btn-accent {
  background: linear-gradient(135deg, var(--accent-color), #0891b2);
  color: white;
  border: none;
  padding: var(--spacing-sm) var(--spacing-md);
  border-radius: var(--radius-md);
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition-normal);
  box-shadow: var(--shadow-sm);
}

.btn-accent:hover {
  background: linear-gradient(135deg, #0891b2, var(--accent-color));
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

.btn-accent:active {
  transform: translateY(0);
  box-shadow: var(--shadow-sm);
}

/* Bottom Tab Navigation */
.bottom-tabs {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  background: var(--bg-card);
  border-top: 1px solid var(--border-light);
  display: flex;
  justify-content: space-around;
  align-items: center;
  padding: var(--spacing-sm) 0;
  box-shadow: 0 -2px 10px rgba(0, 0, 0, 0.1);
  z-index: 1000;
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}

.tab-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: var(--spacing-xs) var(--spacing-sm);
  cursor: pointer;
  transition: all var(--transition-normal);
  border-radius: var(--radius-md);
  min-width: 60px;
  position: relative;
}

.tab-item:hover {
  background: var(--bg-secondary);
  transform: translateY(-2px);
}

.tab-item.active {
  background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
  color: white;
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.tab-item.active::after {
  content: '';
  position: absolute;
  top: -2px;
  left: 50%;
  transform: translateX(-50%);
  width: 20px;
  height: 3px;
  background: var(--primary-color);
  border-radius: 2px;
}

.tab-icon {
  font-size: 1.5rem;
  margin-bottom: var(--spacing-xs);
  transition: all var(--transition-normal);
}

.tab-item.active .tab-icon {
  transform: scale(1.1);
}

.tab-label {
  font-size: 0.75rem;
  font-weight: 500;
  text-align: center;
  line-height: 1;
}

/* Tab Content Sections */
.tab-content {
  display: none;
  padding: var(--spacing-lg);
  margin-bottom: 80px; /* Space for bottom tabs */
}

.tab-content.active {
  display: block;
  animation: fadeIn 0.3s ease;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}

/* Mobile-first adjustments */
@media (max-width: 768px) {
  .bottom-tabs {
    padding: var(--spacing-sm) 0;
  }
  
  .tab-item {
    min-width: 50px;
    padding: var(--spacing-xs);
  }
  
  .tab-icon {
    font-size: 1.25rem;
  }
  
  .tab-label {
    font-size: 0.7rem;
  }
  
  .tab-content {
    padding: var(--spacing-md);
    margin-bottom: 90px;
  }
}

/* Dark theme support */
[data-theme="dark"] .bottom-tabs {
  background: var(--bg-card);
  border-top-color: var(--border-medium);
}

[data-theme="dark"] .tab-item:hover {
  background: var(--bg-tertiary);
}

/* Hide sidebar on mobile when using tabs */
@media (max-width: 768px) {
  .sidebar {
    display: none;
  }
  
  .book-view {
    grid-template-columns: 1fr;
  }
}

/* Tool Grid Layout */
.tools-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: var(--spacing-md);
  padding: var(--spacing-md) 0;
}

.tool-btn {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: var(--spacing-lg);
  background: var(--bg-secondary);
  border: 2px solid var(--border-light);
  border-radius: var(--radius-lg);
  cursor: pointer;
  transition: all var(--transition-normal);
  text-align: center;
  min-height: 100px;
  justify-content: center;
}

.tool-btn:hover {
  border-color: var(--primary-color);
  background: var(--bg-tertiary);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.tool-btn:active {
  transform: translateY(0);
}

.tool-icon {
  font-size: 2rem;
  margin-bottom: var(--spacing-sm);
  display: block;
}

.tool-label {
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--text-secondary);
  line-height: 1.2;
}

/* File Upload Area */
.file-upload-area {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: var(--spacing-xl);
  border: 2px dashed var(--border-medium);
  border-radius: var(--radius-lg);
  cursor: pointer;
  transition: all var(--transition-normal);
  background: var(--bg-secondary);
  text-align: center;
  min-height: 120px;
  justify-content: center;
}

.file-upload-area:hover {
  border-color: var(--primary-color);
  background: var(--bg-tertiary);
  transform: translateY(-1px);
}

.file-upload-area:active {
  transform: translateY(0);
}

.upload-icon {
  font-size: 3rem;
  margin-bottom: var(--spacing-md);
  color: var(--text-muted);
}

.upload-text {
  font-size: 1rem;
  color: var(--text-secondary);
  font-weight: 500;
}

/* Mobile-specific tool adjustments */
@media (max-width: 768px) {
  .tools-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: var(--spacing-sm);
  }
  
  .tool-btn {
    padding: var(--spacing-md);
    min-height: 80px;
  }
  
  .tool-icon {
    font-size: 1.5rem;
  }
  
  .tool-label {
    font-size: 0.8rem;
  }
  
  .file-upload-area {
    padding: var(--spacing-lg);
    min-height: 100px;
  }
  
  .upload-icon {
    font-size: 2.5rem;
  }
  
  .upload-text {
    font-size: 0.9rem;
  }
}

/* AI Tab Styling */
.ai-section {
  background: var(--bg-card);
  border-radius: var(--radius-lg);
  padding: var(--spacing-lg);
  margin-bottom: var(--spacing-lg);
  border: 1px solid var(--border-light);
  box-shadow: var(--shadow-sm);
}

.ai-section h3 {
  margin: 0 0 var(--spacing-md) 0;
  color: var(--text-primary);
  font-size: 1.5rem;
}

.ai-controls {
  display: flex;
  gap: var(--spacing-md);
  margin-bottom: var(--spacing-lg);
  flex-wrap: wrap;
}

.ai-highlights {
  background: var(--bg-secondary);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  padding: var(--spacing-lg);
  min-height: 200px;
  white-space: pre-wrap;
  font-family: var(--font-mono);
  line-height: 1.6;
  color: var(--text-primary);
}

/* Study Notes Integration */
.study-notes-container {
  margin-top: var(--spacing-lg);
  padding-top: var(--spacing-lg);
  border-top: 1px solid var(--border-light);
}

.study-notes-section h4 {
  margin: 0 0 var(--spacing-md) 0;
  color: var(--text-primary);
  font-size: 1.2rem;
}

.study-note-item {
  background: var(--bg-secondary);
  border: 1px solid var(--border-light);
  border-radius: var(--radius-lg);
  padding: var(--spacing-md);
  margin-bottom: var(--spacing-sm);
  cursor: pointer;
  transition: all 0.2s ease;
}

.study-note-item:hover {
  background: var(--bg-secondary);
  border-color: var(--accent-color);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.note-title {
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: var(--spacing-xs);
  font-size: 1.1rem;
}

.note-content {
  color: var(--text-secondary);
  margin-bottom: var(--spacing-xs);
  line-height: 1.5;
}

.note-tags {
  display: flex;
  gap: var(--spacing-xs);
  flex-wrap: wrap;
}

.tag {
  background: var(--accent-color);
  color: white;
  padding: 2px 8px;
  border-radius: 12px;
  font-size: 0.8rem;
  font-weight: 500;
}

/* Button Styling */
.btn-accent {
  background: linear-gradient(135deg, var(--accent-color), #0891b2);
  color: white;
  border: none;
  padding: var(--spacing-sm) var(--spacing-lg);
  border-radius: var(--radius-lg);
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s ease;
  box-shadow: var(--shadow-sm);
}

.btn-accent:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.btn-accent:active {
  transform: translateY(0);
}

.btn-accent.loading {
  opacity: 0.7;
  cursor: not-allowed;
}

.btn-secondary {
  background: var(--bg-secondary);
  color: var(--text-primary);
  border: 1px solid var(--border-light);
  padding: var(--spacing-sm) var(--spacing-lg);
  border-radius: var(--radius-lg);
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s ease;
}

.btn-secondary:hover {
  background: var(--bg-secondary);
  border-color: var(--accent-color);
}

/* Enhanced Camera Interface Styles */
.camera-interface {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  margin-top: 1rem;
}

.camera-viewport {
  position: relative;
  width: 100%;
  max-width: 600px;
  margin: 0 auto;
  border-radius: 12px;
  overflow: hidden;
  background: #000;
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
}

.camera-viewport video {
  width: 100%;
  height: auto;
  display: block;
  border-radius: 12px;
}

.camera-viewport canvas {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  border-radius: 12px;
}

/* Camera Overlays */
.camera-overlays {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
}

/* Focus Guide */
.focus-guide {
  position: absolute;
  top: 10%;
  left: 10%;
  width: 80%;
  height: 80%;
  pointer-events: none;
}

.focus-guide .corner {
  position: absolute;
  width: 30px;
  height: 30px;
  border: 3px solid rgba(255, 255, 255, 0.8);
  border-radius: 4px;
}

.focus-guide .top-left {
  top: 0;
  left: 0;
  border-right: none;
  border-bottom: none;
}

.focus-guide .top-right {
  top: 0;
  right: 0;
  border-left: none;
  border-bottom: none;
}

.focus-guide .bottom-left {
  bottom: 0;
  left: 0;
  border-right: none;
  border-top: none;
}

.focus-guide .bottom-right {
  bottom: 0;
  right: 0;
  border-left: none;
  border-top: none;
}

.focus-guide .center-line {
  position: absolute;
  background: rgba(255, 255, 255, 0.3);
}

.focus-guide .horizontal {
  top: 50%;
  left: 0;
  width: 100%;
  height: 1px;
  transform: translateY(-50%);
}

.focus-guide .vertical {
  left: 50%;
  top: 0;
  width: 1px;
  height: 100%;
  transform: translateX(-50%);
}

/* Reading Mode Overlay */
.reading-mode-overlay {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
}

.reading-line {
  position: absolute;
  top: 50%;
  left: 0;
  width: 100%;
  height: 2px;
  background: linear-gradient(90deg, transparent, #6366f1, transparent);
  transform: translateY(-50%);
  animation: reading-pulse 2s ease-in-out infinite;
}

.reading-overlay-progress {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: linear-gradient(180deg, 
    rgba(99, 102, 241, 0.1) 0%, 
    transparent 40%, 
    transparent 60%, 
    rgba(99, 102, 241, 0.1) 100%);
  pointer-events: none;
}

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

/* Camera Controls Overlay */
.camera-controls-overlay {
  position: absolute;
  bottom: 20px;
  left: 0;
  width: 100%;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 0 20px;
  pointer-events: auto;
}

.camera-controls-left,
.camera-controls-right {
  display: flex;
  gap: 10px;
}

.camera-control-btn {
  width: 50px;
  height: 50px;
  border-radius: 50%;
  border: 2px solid rgba(255, 255, 255, 0.8);
  background: rgba(0, 0, 0, 0.6);
  color: white;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all 0.3s ease;
  backdrop-filter: blur(10px);
}

.camera-control-btn:hover {
  background: rgba(99, 102, 241, 0.8);
  border-color: #6366f1;
  transform: scale(1.1);
}

.camera-control-btn.active {
  background: #6366f1;
  border-color: #6366f1;
}

.control-icon {
  font-size: 18px;
}

/* Capture Button */
.capture-btn {
  width: 80px;
  height: 80px;
  border-radius: 50%;
  border: 4px solid rgba(255, 255, 255, 0.9);
  background: rgba(255, 255, 255, 0.2);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  transition: all 0.3s ease;
  backdrop-filter: blur(10px);
}

.capture-btn:hover {
  background: rgba(255, 255, 255, 0.3);
  transform: scale(1.05);
}

.capture-btn:active {
  transform: scale(0.95);
}

.capture-btn-inner {
  width: 60px;
  height: 60px;
  border-radius: 50%;
  background: #6366f1;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.3s ease;
}

.capture-btn:hover .capture-btn-inner {
  background: #4f46e5;
}

.capture-icon {
  font-size: 24px;
  color: white;
}

/* Camera Info Overlay */
.camera-info-overlay {
  position: absolute;
  top: 20px;
  left: 20px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  pointer-events: auto;
}

.camera-info-item {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 6px 12px;
  background: rgba(0, 0, 0, 0.7);
  border-radius: 20px;
  color: white;
  font-size: 12px;
  backdrop-filter: blur(10px);
}

.info-icon {
  font-size: 14px;
}

.info-text {
  font-weight: 500;
}

/* Camera Settings Panel */
.camera-settings-panel {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
  padding: 1rem;
  background: var(--card-bg);
  border-radius: 12px;
  border: 1px solid var(--border-color);
}

.settings-section h4 {
  margin: 0 0 1rem 0;
  color: var(--text-primary);
  font-size: 14px;
  font-weight: 600;
}

.setting-group {
  margin-bottom: 1rem;
}

.setting-group label {
  display: block;
  margin-bottom: 0.5rem;
  color: var(--text-secondary);
  font-size: 12px;
  font-weight: 500;
}

.setting-select {
  width: 100%;
  padding: 8px 12px;
  border: 1px solid var(--border-color);
  border-radius: 8px;
  background: var(--input-bg);
  color: var(--text-primary);
  font-size: 14px;
  transition: border-color 0.3s ease;
}

.setting-select:focus {
  outline: none;
  border-color: var(--primary-color);
}

/* Checkbox Styles */
.checkbox-label {
  display: flex;
  align-items: center;
  gap: 8px;
  cursor: pointer;
  font-size: 14px;
  color: var(--text-primary);
}

.checkbox-label input[type="checkbox"] {
  display: none;
}

.checkmark {
  width: 18px;
  height: 18px;
  border: 2px solid var(--border-color);
  border-radius: 4px;
  position: relative;
  transition: all 0.3s ease;
}

.checkbox-label input[type="checkbox"]:checked + .checkmark {
  background: var(--primary-color);
  border-color: var(--primary-color);
}

.checkbox-label input[type="checkbox"]:checked + .checkmark::after {
  content: '✓';
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  color: white;
  font-size: 12px;
  font-weight: bold;
}

/* Mobile Responsive */
@media (max-width: 768px) {
  .camera-settings-panel {
    grid-template-columns: 1fr;
  }
  
  .camera-controls-overlay {
    bottom: 10px;
    padding: 0 10px;
  }
  
  .camera-control-btn {
    width: 45px;
    height: 45px;
  }
  
  .capture-btn {
    width: 70px;
    height: 70px;
  }
  
  .capture-btn-inner {
    width: 50px;
    height: 50px;
  }
  
  .camera-info-overlay {
    top: 10px;
    left: 10px;
  }
  
  .camera-info-item {
    padding: 4px 8px;
    font-size: 11px;
  }
}

/* Reading Mode Active Styles */
.reading-mode-active .focus-guide {
  display: none;
}

.reading-mode-active .reading-mode-overlay {
  display: block;
}

.reading-mode-active .camera-viewport {
  border: 3px solid #6366f1;
}

/* Enhanced Button Styles */
.btn-accent {
  background: linear-gradient(135deg, #6366f1, #8b5cf6);
  color: white;
  border: none;
  transition: all 0.3s ease;
}

.btn-accent:hover {
  background: linear-gradient(135deg, #4f46e5, #7c3aed);
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(99, 102, 241, 0.3);
}

.btn-accent.active {
  background: linear-gradient(135deg, #dc2626, #b91c1c);
}

/* Loading States */
.capture-btn.loading {
  pointer-events: none;
  opacity: 0.7;
}

.capture-btn.loading .capture-btn-inner {
  animation: pulse 1.5s ease-in-out infinite;
}

@keyframes pulse {
  0%, 100% { transform: scale(1); }
  50% { transform: scale(0.9); }
}