/* Main Styles - Mobile First */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --primary-color: #FF6B35;
  --primary-dark: #E55A2B;
  --primary-light: #FF8C5A;
  --secondary-color: #4ECDC4;
  --background: #FFFEF7;
  --surface: #FFFFFF;
  --text-primary: #2C1810;
  --text-secondary: #5C4033;
  --border-color: #E0E0E0;
  --success-color: #4CAF50;
  --error-color: #F44336;
  --warning-color: #FFC107;
  --info-color: #2196F3;
  --accent-yellow: #FFD700;
  --accent-pink: #FF69B4;
  --accent-blue: #42A5F5;
  
  --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.1);
  --shadow-md: 0 4px 8px rgba(0, 0, 0, 0.15);
  --shadow-lg: 0 8px 16px rgba(0, 0, 0, 0.2);
  
  --border-radius: 12px;
  --border-radius-sm: 8px;
  --border-radius-lg: 16px;
  
  --spacing-xs: 4px;
  --spacing-sm: 8px;
  --spacing-md: 16px;
  --spacing-lg: 24px;
  --spacing-xl: 32px;
}

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen',
    'Ubuntu', 'Cantarell', 'Fira Sans', 'Droid Sans', 'Helvetica Neue',
    sans-serif;
  background-color: var(--background);
  color: var(--text-primary);
  line-height: 1.6;
  overflow-x: hidden;
  /* Prevent zoom on double-tap iOS */
  touch-action: manipulation;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
  font-weight: 600;
  line-height: 1.2;
  margin-bottom: var(--spacing-md);
  color: var(--text-primary);
}

h1 { font-size: 1.75rem; }
h2 { font-size: 1.5rem; }
h3 { font-size: 1.25rem; }
h4 { font-size: 1.125rem; }

p {
  margin-bottom: var(--spacing-md);
}

a {
  color: var(--primary-color);
  text-decoration: none;
  transition: color 0.3s ease;
}

a:hover {
  color: var(--primary-dark);
}

/* Layout */
.app-header {
  background: var(--surface);
  box-shadow: var(--shadow-sm);
  padding: var(--spacing-md);
  display: flex;
  justify-content: space-between;
  align-items: center;
  position: sticky;
  top: 0;
  z-index: 100;
}

.app-title {
  font-size: 1.5rem;
  margin: 0;
  color: var(--primary-color);
}

.main-content {
  max-width: 1200px;
  margin: 0 auto;
  padding: var(--spacing-md);
  min-height: calc(100vh - 80px);
}

/* Sidebar */
.sidebar {
  position: fixed;
  top: 0;
  left: -100%;
  width: 280px;
  height: 100vh;
  background: var(--surface);
  box-shadow: var(--shadow-lg);
  z-index: 1000;
  transition: left 0.3s ease;
  overflow-y: auto;
}

.sidebar.open {
  left: 0;
}

.sidebar-header {
  padding: var(--spacing-lg);
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-bottom: 1px solid var(--border-color);
}

.sidebar-header h2 {
  margin: 0;
  font-size: 1.25rem;
}

.nav-menu {
  list-style: none;
  padding: var(--spacing-md);
}

.nav-menu li {
  margin-bottom: var(--spacing-xs);
}

.nav-link {
  display: block;
  padding: var(--spacing-md);
  border-radius: var(--border-radius-sm);
  transition: background-color 0.3s ease;
  color: var(--text-primary);
}

.nav-link:hover,
.nav-link.active {
  background-color: rgba(139, 69, 19, 0.1);
  color: var(--primary-color);
}

/* Overlay */
.overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.5);
  z-index: 999;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.3s ease, visibility 0.3s ease;
}

.overlay.active {
  opacity: 1;
  visibility: visible;
}

/* Pages */
.page {
  display: none;
  animation: fadeIn 0.3s ease;
}

.page.active {
  display: block;
}

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

/* Welcome Section */
.welcome-section {
  text-align: center;
  padding: var(--spacing-xl) var(--spacing-md);
}

.welcome-section h2 {
  font-size: 2rem;
  margin-bottom: var(--spacing-sm);
}

.subtitle {
  font-size: 1.125rem;
  color: var(--text-secondary);
  margin-bottom: var(--spacing-xl);
}

/* Feature Grid */
.feature-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: var(--spacing-lg);
  margin: var(--spacing-xl) 0;
}

.feature-card {
  background: linear-gradient(135deg, #FFFFFF 0%, #FFF9E6 100%);
  padding: var(--spacing-lg);
  border-radius: var(--border-radius-lg);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
  text-align: center;
  transition: transform 0.3s ease, box-shadow 0.3s ease;
  border: 2px solid transparent;
}

.feature-card:hover {
  transform: translateY(-6px) scale(1.02);
  box-shadow: 0 8px 20px rgba(0, 0, 0, 0.15);
  border-color: var(--primary-color);
}

.feature-icon {
  font-size: 3rem;
  margin-bottom: var(--spacing-md);
}

.feature-card h3 {
  margin-bottom: var(--spacing-sm);
}

.feature-card p {
  color: var(--text-secondary);
  font-size: 0.9rem;
}

/* Lesson Content */
.lesson-header {
  margin-bottom: var(--spacing-xl);
}

.lesson-description {
  color: var(--text-secondary);
  font-size: 1.125rem;
}

.lesson-content {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-lg);
}

/* Practice Section */
.practice-section {
  padding: var(--spacing-md);
}

.practice-header {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
  margin-bottom: var(--spacing-lg);
}

.character-info {
  background: var(--surface);
  padding: var(--spacing-lg);
  border-radius: var(--border-radius);
  box-shadow: var(--shadow-md);
  margin-bottom: var(--spacing-lg);
}

.char-display {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--spacing-md);
}

.hanzi {
  font-size: 4rem;
  font-weight: 600;
  color: var(--primary-color);
}

.char-details {
  text-align: center;
  width: 100%;
}

.char-details p {
  margin-bottom: var(--spacing-sm);
  font-size: 1rem;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-xs);
  flex-wrap: wrap;
}

/* Character Info Card */
.character-info-card {
  background: linear-gradient(135deg, #FFF9C4 0%, #FFE082 100%);
  padding: var(--spacing-lg);
  border-radius: var(--border-radius-lg);
  box-shadow: var(--shadow-md);
  margin-bottom: var(--spacing-lg);
  border: 3px solid var(--primary-color);
}

.char-display-large {
  text-align: center;
}

.hanzi-large-display {
  font-size: 5rem;
  font-weight: 600;
  color: var(--primary-color);
  display: block;
  margin-bottom: var(--spacing-md);
  text-shadow: 2px 2px 4px rgba(0,0,0,0.1);
}

.char-details-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: var(--spacing-md);
  margin-bottom: var(--spacing-md);
}

.char-detail-item {
  display: flex;
  align-items: center;
  gap: var(--spacing-xs);
  flex-wrap: wrap;
  justify-content: center;
}

.detail-label {
  font-weight: 600;
  color: var(--text-secondary);
}

.detail-value {
  color: var(--primary-color);
  font-weight: 500;
}

/* Practice Mode Selector */
.practice-mode-selector {
  background: var(--surface);
  padding: var(--spacing-lg);
  border-radius: var(--border-radius);
  box-shadow: var(--shadow-sm);
  margin-bottom: var(--spacing-lg);
}

.practice-mode-selector h4 {
  text-align: center;
  margin-bottom: var(--spacing-md);
  color: var(--primary-color);
}

.mode-buttons {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
  gap: var(--spacing-md);
}

.btn-mode {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: var(--spacing-md);
  border: 3px solid var(--border-color);
  background: var(--surface);
  border-radius: var(--border-radius);
  transition: all 0.3s ease;
  cursor: pointer;
}

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

.btn-mode.active {
  border-color: var(--primary-color);
  background: linear-gradient(135deg, rgba(255, 107, 53, 0.1) 0%, rgba(255, 107, 53, 0.05) 100%);
  box-shadow: var(--shadow-md);
}

.mode-icon {
  font-size: 2.5rem;
  margin-bottom: var(--spacing-xs);
}

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

.mode-desc {
  font-size: 0.85rem;
  color: var(--text-secondary);
  text-align: center;
}

/* Canvas Wrapper */
.canvas-wrapper {
  background: var(--surface);
  padding: var(--spacing-lg);
  border-radius: var(--border-radius-lg);
  box-shadow: var(--shadow-md);
  margin-bottom: var(--spacing-lg);
}

.canvas-container {
  position: relative;
  margin: 0 auto var(--spacing-md);
  max-width: 500px;
  min-height: 400px;
  background: #FAFAFA;
  border-radius: var(--border-radius);
  padding: var(--spacing-md);
  display: flex;
  align-items: center;
  justify-content: center;
}

/* Ensure both canvases are positioned correctly */
.canvas-container canvas {
  position: absolute;
  top: var(--spacing-md);
  left: var(--spacing-md);
  right: var(--spacing-md);
  bottom: var(--spacing-md);
}

.canvas-label {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  color: var(--text-secondary);
  font-size: 1.2rem;
  pointer-events: none;
  opacity: 0.5;
  z-index: 3;
  transition: opacity 0.3s;
  background: rgba(255, 255, 255, 0.8);
  padding: 8px 16px;
  border-radius: 8px;
}

.canvas-container.has-content .canvas-label,
.canvas-container:has(canvas:not(:empty)) .canvas-label {
  opacity: 0;
}

#practice-canvas {
  width: 100% !important;
  max-width: 400px !important;
  height: auto !important;
  aspect-ratio: 1;
  min-height: 300px;
  border: 4px solid var(--primary-color);
  border-radius: var(--border-radius-lg);
  box-shadow: 0 8px 16px rgba(0, 0, 0, 0.15);
  background: #FFFFFF !important;
  display: block !important;
  margin: 0 auto;
  touch-action: none;
  cursor: crosshair;
  position: relative;
  z-index: 2;
  visibility: visible !important;
  opacity: 1 !important;
}

#trace-overlay-canvas {
  position: absolute;
  top: var(--spacing-md);
  left: var(--spacing-md);
  width: calc(100% - 32px) !important;
  max-width: 400px !important;
  height: auto !important;
  aspect-ratio: 1;
  min-height: 300px;
  pointer-events: none;
  z-index: 1;
  opacity: 0;
  transition: opacity 0.5s ease;
  display: block !important;
  visibility: visible !important;
  background: transparent !important;
}

#trace-overlay-canvas.active {
  opacity: 1 !important;
  visibility: visible !important;
}

#practice-canvas:active {
  cursor: crosshair;
}

.canvas-controls-panel {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(100px, 1fr));
  gap: var(--spacing-sm);
  margin-top: var(--spacing-md);
}

.btn-control {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: var(--spacing-sm) var(--spacing-md);
  background: var(--surface);
  border: 2px solid var(--primary-color);
  color: var(--primary-color);
  border-radius: var(--border-radius);
  font-size: 0.9rem;
  transition: all 0.3s ease;
  min-height: 60px;
}

.btn-control:hover {
  background: var(--primary-color);
  color: white;
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.btn-control.active {
  background: var(--primary-color);
  color: white;
  box-shadow: var(--shadow-md);
}

.control-icon {
  font-size: 1.5rem;
  margin-bottom: 4px;
}

.control-text {
  font-size: 0.85rem;
  font-weight: 500;
}

/* Stroke Counter */
.stroke-counter {
  display: flex;
  gap: var(--spacing-sm);
  justify-content: center;
  margin: var(--spacing-lg) 0;
  flex-wrap: wrap;
}

.stroke-dot {
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--border-color);
  transition: all 0.3s ease;
}

.stroke-dot.active {
  background: var(--primary-color);
  transform: scale(1.3);
}

.stroke-dot.correct {
  background: var(--success-color);
}

.stroke-dot.wrong {
  background: var(--error-color);
}

/* Practice Controls */
.practice-controls {
  display: flex;
  gap: var(--spacing-md);
  justify-content: center;
  flex-wrap: wrap;
  margin-top: var(--spacing-lg);
}

/* Quick Start */
.quick-start {
  margin-top: var(--spacing-xl);
  padding: var(--spacing-xl);
  background: linear-gradient(135deg, #FFE082 0%, #FFF9C4 100%);
  border-radius: var(--border-radius-lg);
  box-shadow: var(--shadow-lg);
  text-align: center;
  border: 3px solid var(--primary-color);
}

.quick-start h3 {
  color: var(--primary-color);
  font-size: 1.75rem;
  margin-bottom: var(--spacing-md);
}

.quick-start-desc {
  color: var(--text-secondary);
  font-size: 1.125rem;
  margin-bottom: var(--spacing-lg);
}

/* Responsive */
@media (min-width: 768px) {
  html {
    font-size: 18px;
  }
  
  .main-content {
    padding: var(--spacing-xl);
  }
  
  .feature-grid {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .char-display {
    flex-direction: row;
    justify-content: space-around;
  }
  
  .hanzi {
    font-size: 5rem;
  }
}

@media (min-width: 1024px) {
  .feature-grid {
    grid-template-columns: repeat(4, 1fr);
  }
}

/* Print Styles */
@media print {
  .app-header,
  .sidebar,
  .overlay,
  .practice-controls,
  .canvas-controls {
    display: none;
  }
  
  .main-content {
    max-width: 100%;
    padding: 0;
  }
}