/* Snowboard Physics Simulator - Premium Visual Design */

@import url('https://fonts.googleapis.com/css2?family=Space+Grotesk:wght@400;500;600;700&family=Inter:wght@400;500;600&display=swap');

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

:root {
  /* Core palette */
  --bg-deep: #0a0e14;
  --bg-dark: #0d1117;
  --bg-card: rgba(22, 27, 34, 0.8);
  --bg-glass: rgba(30, 37, 46, 0.6);
  --bg-glass-light: rgba(45, 55, 72, 0.4);
  
  /* Text */
  --text-primary: #f0f6fc;
  --text-secondary: #8b949e;
  --text-muted: #484f58;
  
  /* Accents */
  --accent-primary: #58a6ff;
  --accent-secondary: #3fb950;
  --accent-warning: #d29922;
  --accent-danger: #f85149;
  
  /* Board colors */
  --board-a: #ff6b6b;
  --board-a-glow: rgba(255, 107, 107, 0.4);
  --board-b: #4ecdc4;
  --board-b-glow: rgba(78, 205, 196, 0.4);
  
  /* Gradients */
  --gradient-primary: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  --gradient-warm: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
  --gradient-cool: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);
  --gradient-dark: linear-gradient(180deg, #0d1117 0%, #161b22 100%);
  
  /* Effects */
  --blur-amount: 20px;
  --border-glass: 1px solid rgba(255, 255, 255, 0.08);
  --shadow-soft: 0 8px 32px rgba(0, 0, 0, 0.4);
  --shadow-glow: 0 0 40px rgba(88, 166, 255, 0.15);
  
  /* Timing */
  --transition-fast: 0.15s ease;
  --transition-smooth: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-bounce: 0.5s cubic-bezier(0.34, 1.56, 0.64, 1);
}

/* Base */
body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  background: var(--bg-deep);
  color: var(--text-primary);
  min-height: 100vh;
  overflow-x: hidden;
  line-height: 1.5;
}

/* Animated background */
body::before {
  content: '';
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: 
    radial-gradient(ellipse at 20% 20%, rgba(102, 126, 234, 0.15) 0%, transparent 50%),
    radial-gradient(ellipse at 80% 80%, rgba(118, 75, 162, 0.1) 0%, transparent 50%),
    radial-gradient(ellipse at 50% 50%, rgba(78, 205, 196, 0.05) 0%, transparent 70%);
  pointer-events: none;
  z-index: -1;
}

#app {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

/* ==================== HEADER ==================== */
.header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 16px 32px;
  background: var(--bg-glass);
  backdrop-filter: blur(var(--blur-amount));
  -webkit-backdrop-filter: blur(var(--blur-amount));
  border-bottom: var(--border-glass);
  position: sticky;
  top: 0;
  z-index: 100;
}

.logo {
  display: flex;
  align-items: center;
  gap: 14px;
}

.logo-icon {
  font-size: 32px;
  filter: drop-shadow(0 0 10px rgba(78, 205, 196, 0.5));
  animation: float 3s ease-in-out infinite;
}

@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-4px); }
}

.logo h1 {
  font-family: 'Space Grotesk', sans-serif;
  font-size: 22px;
  font-weight: 700;
  letter-spacing: -0.5px;
  background: linear-gradient(135deg, #fff 0%, #a8b2d1 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* Skill Toggle */
.skill-toggle {
  display: flex;
  gap: 4px;
  background: var(--bg-dark);
  padding: 4px;
  border-radius: 12px;
  border: var(--border-glass);
}

.skill-btn {
  padding: 10px 20px;
  border: none;
  background: transparent;
  color: var(--text-secondary);
  font-size: 13px;
  font-weight: 600;
  border-radius: 8px;
  cursor: pointer;
  transition: all var(--transition-smooth);
  position: relative;
  overflow: hidden;
}

.skill-btn::before {
  content: '';
  position: absolute;
  inset: 0;
  background: var(--gradient-cool);
  opacity: 0;
  transition: opacity var(--transition-smooth);
}

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

.skill-btn.active {
  color: var(--bg-dark);
}

.skill-btn.active::before {
  opacity: 1;
}

.skill-btn span {
  position: relative;
  z-index: 1;
}

/* ==================== MAIN LAYOUT ==================== */
.main-container {
  display: grid;
  grid-template-columns: 300px 1fr 320px;
  flex: 1;
  gap: 0;
}

/* ==================== PANELS ==================== */
.panel {
  background: var(--bg-glass);
  backdrop-filter: blur(var(--blur-amount));
  -webkit-backdrop-filter: blur(var(--blur-amount));
  padding: 20px;
  overflow-y: auto;
  max-height: calc(100vh - 120px);
}

.panel::-webkit-scrollbar {
  width: 6px;
}

.panel::-webkit-scrollbar-track {
  background: transparent;
}

.panel::-webkit-scrollbar-thumb {
  background: var(--bg-glass-light);
  border-radius: 3px;
}

.left-panel {
  border-right: var(--border-glass);
}

.right-panel {
  border-left: var(--border-glass);
}

.panel-section {
  background: var(--bg-card);
  backdrop-filter: blur(10px);
  border-radius: 16px;
  padding: 20px;
  margin-bottom: 16px;
  border: var(--border-glass);
  transition: all var(--transition-smooth);
}

.panel-section:hover {
  border-color: rgba(255, 255, 255, 0.12);
  box-shadow: var(--shadow-soft);
}

.panel-section h3 {
  font-family: 'Space Grotesk', sans-serif;
  font-size: 11px;
  font-weight: 700;
  color: var(--text-muted);
  margin-bottom: 16px;
  text-transform: uppercase;
  letter-spacing: 1.5px;
}

/* ==================== INPUTS ==================== */
.input-group {
  margin-bottom: 18px;
}

.input-group label {
  display: block;
  font-size: 12px;
  color: var(--text-secondary);
  margin-bottom: 8px;
  font-weight: 500;
}

.input-group input,
.input-group select {
  width: 100%;
  padding: 12px 14px;
  background: var(--bg-dark);
  border: 1px solid rgba(255, 255, 255, 0.06);
  border-radius: 10px;
  color: var(--text-primary);
  font-size: 14px;
  font-weight: 500;
  transition: all var(--transition-smooth);
}

.input-group input:focus,
.input-group select:focus {
  outline: none;
  border-color: var(--accent-primary);
  box-shadow: 0 0 0 3px rgba(88, 166, 255, 0.15);
}

.input-group select {
  cursor: pointer;
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' fill='%238b949e' viewBox='0 0 16 16'%3E%3Cpath d='M8 11L3 6h10l-5 5z'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 14px center;
  padding-right: 36px;
}

.height-inputs,
.weight-input {
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--text-secondary);
  font-size: 13px;
}

.height-inputs input {
  width: 65px;
  text-align: center;
}

.weight-input input {
  width: 85px;
}

/* ==================== BUTTONS ==================== */
.recommend-btn {
  width: 100%;
  padding: 16px 24px;
  background: var(--gradient-cool);
  border: none;
  border-radius: 12px;
  color: var(--bg-dark);
  font-size: 14px;
  font-weight: 700;
  cursor: pointer;
  transition: all var(--transition-smooth);
  position: relative;
  overflow: hidden;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.recommend-btn::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255,255,255,0.3), transparent);
  transition: left 0.5s;
}

.recommend-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 25px rgba(79, 172, 254, 0.4);
}

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

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

/* ==================== RECOMMENDATIONS ==================== */
.ideal-length {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  padding: 16px;
  background: linear-gradient(135deg, rgba(79, 172, 254, 0.1) 0%, rgba(0, 242, 254, 0.05) 100%);
  border-radius: 12px;
  margin-bottom: 16px;
  border: 1px solid rgba(79, 172, 254, 0.2);
}

.ideal-length .label {
  color: var(--text-secondary);
  font-size: 12px;
  font-weight: 500;
}

.ideal-length .value {
  font-family: 'Space Grotesk', sans-serif;
  font-size: 32px;
  font-weight: 700;
  background: var(--gradient-cool);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.recommendations-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.recommendation-card {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 14px;
  background: var(--bg-dark);
  border-radius: 12px;
  cursor: pointer;
  transition: all var(--transition-smooth);
  border: 1px solid transparent;
}

.recommendation-card:hover {
  background: var(--bg-glass-light);
  border-color: rgba(255, 255, 255, 0.1);
  transform: translateX(4px);
}

.recommendation-card .rank {
  width: 28px;
  height: 28px;
  background: var(--gradient-cool);
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 12px;
  font-weight: 700;
  color: var(--bg-dark);
}

.recommendation-card .info {
  flex: 1;
}

.recommendation-card .brand {
  font-size: 10px;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.5px;
  font-weight: 600;
}

.recommendation-card .model {
  font-size: 14px;
  font-weight: 600;
  margin-top: 2px;
}

.recommendation-card .size {
  font-family: 'Space Grotesk', sans-serif;
  font-size: 14px;
  color: var(--board-b);
  font-weight: 700;
}

/* ==================== SIMULATOR ==================== */
.simulator-container {
  display: flex;
  flex-direction: column;
  background: transparent;
  position: relative;
}

#canvas-container {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  min-height: 400px;
}

#canvas-container canvas {
  display: block;
  border-radius: 0;
}

/* Simulator Controls */
.simulator-controls {
  background: var(--bg-glass);
  backdrop-filter: blur(var(--blur-amount));
  padding: 20px 28px;
  border-top: var(--border-glass);
}

.board-selectors {
  display: flex;
  gap: 40px;
  margin-bottom: 20px;
}

.board-selector {
  flex: 1;
}

.board-label {
  font-family: 'Space Grotesk', sans-serif;
  font-size: 11px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 1px;
}

.board-selector select {
  width: 100%;
  padding: 10px 14px;
  background: var(--bg-dark);
  border: 1px solid rgba(255, 255, 255, 0.06);
  border-radius: 8px;
  color: var(--text-primary);
  font-size: 13px;
  margin: 10px 0;
  cursor: pointer;
}

.slider-row {
  display: flex;
  align-items: center;
  gap: 14px;
}

.slider-row input[type="range"] {
  flex: 1;
  height: 6px;
  -webkit-appearance: none;
  background: var(--bg-dark);
  border-radius: 3px;
  cursor: pointer;
}

.slider-row input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 20px;
  height: 20px;
  background: var(--board-b);
  border-radius: 50%;
  cursor: pointer;
  box-shadow: 0 0 15px var(--board-b-glow);
  transition: all var(--transition-smooth);
}

.slider-row input[type="range"]::-webkit-slider-thumb:hover {
  transform: scale(1.15);
}

#boardSliderA::-webkit-slider-thumb {
  background: var(--board-a);
  box-shadow: 0 0 15px var(--board-a-glow);
}

.slider-value {
  font-family: 'Space Grotesk', sans-serif;
  font-size: 15px;
  font-weight: 700;
  min-width: 65px;
  text-align: right;
}

/* Scenario & Terrain Selectors */
.scenario-selector {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 14px;
  flex-wrap: wrap;
}

.scenario-selector > span {
  font-size: 11px;
  color: var(--text-muted);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.scenario-btn {
  padding: 6px 14px;
  border: 1px solid rgba(255, 255, 255, 0.15);
  background: rgba(255, 255, 255, 0.05);
  color: var(--text-secondary);
  font-size: 11px;
  font-weight: 600;
  border-radius: 16px;
  cursor: pointer;
  transition: all var(--transition-smooth);
}

.scenario-btn:hover {
  background: rgba(255, 255, 255, 0.1);
  border-color: rgba(255, 255, 255, 0.25);
  color: var(--text-primary);
}

.scenario-btn.active {
  background: linear-gradient(135deg, var(--accent-primary), var(--accent-secondary));
  border-color: transparent;
  color: white;
}

.replay-btn {
  padding: 6px 12px;
  border: 1px solid rgba(255, 255, 255, 0.2);
  background: rgba(78, 205, 196, 0.15);
  color: var(--accent-secondary);
  font-size: 12px;
  font-weight: 600;
  border-radius: 16px;
  cursor: pointer;
  transition: all var(--transition-smooth);
}

.replay-btn:hover {
  background: rgba(78, 205, 196, 0.25);
  border-color: var(--accent-secondary);
}

.terrain-selector {
  display: flex;
  align-items: center;
  gap: 14px;
  margin-bottom: 14px;
}

.terrain-selector > span {
  font-size: 11px;
  color: var(--text-muted);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.terrain-btn {
  padding: 8px 18px;
  border: 1px solid rgba(255, 255, 255, 0.1);
  background: transparent;
  color: var(--text-secondary);
  font-size: 12px;
  font-weight: 600;
  border-radius: 20px;
  cursor: pointer;
  transition: all var(--transition-smooth);
}

.terrain-btn:hover {
  border-color: var(--board-b);
  color: var(--text-primary);
}

.terrain-btn.active {
  background: var(--board-b);
  border-color: var(--board-b);
  color: var(--bg-dark);
  box-shadow: 0 0 20px var(--board-b-glow);
}

.viz-toggles {
  display: flex;
  gap: 24px;
}

.viz-toggles label {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 12px;
  color: var(--text-secondary);
  cursor: pointer;
  transition: color var(--transition-fast);
}

.viz-toggles label:hover {
  color: var(--text-primary);
}

.viz-toggles input[type="checkbox"] {
  width: 16px;
  height: 16px;
  accent-color: var(--board-b);
  cursor: pointer;
}

/* ==================== BOARD DETAILS ==================== */
.board-detail {
  padding: 0;
  overflow: hidden;
}

.board-header {
  padding: 18px 20px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  position: relative;
}

.board-header::before {
  content: '';
  position: absolute;
  inset: 0;
  background: inherit;
  filter: blur(20px);
  opacity: 0.5;
  z-index: -1;
}

.board-header h3 {
  color: white;
  margin: 0;
  font-size: 11px;
  opacity: 0.8;
}

.board-name {
  font-family: 'Space Grotesk', sans-serif;
  font-size: 14px;
  font-weight: 700;
  color: white;
}

.board-stats {
  padding: 18px 20px;
}

.stat-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 10px 0;
  border-bottom: 1px solid rgba(255, 255, 255, 0.04);
}

.stat-row:last-of-type {
  border-bottom: none;
}

.stat-label {
  font-size: 12px;
  color: var(--text-muted);
}

.stat-value {
  font-family: 'Space Grotesk', sans-serif;
  font-size: 14px;
  font-weight: 600;
}

.expert-stat {
  display: none;
}

body.skill-expert .expert-stat,
body.skill-intermediate .expert-stat {
  display: flex;
}

/* Stability Indicator */
.stability-indicator {
  margin-top: 18px;
  padding-top: 18px;
  border-top: 1px solid rgba(255, 255, 255, 0.04);
}

.stability-label {
  display: block;
  text-align: center;
  font-family: 'Space Grotesk', sans-serif;
  font-size: 14px;
  font-weight: 700;
  margin-bottom: 12px;
  letter-spacing: 1px;
}

.stability-bar {
  height: 8px;
  background: linear-gradient(90deg, 
    var(--board-a) 0%, 
    var(--accent-warning) 50%, 
    var(--accent-secondary) 100%
  );
  border-radius: 4px;
  position: relative;
  overflow: visible;
}

.stability-fill {
  position: absolute;
  top: -4px;
  height: 16px;
  width: 16px;
  background: white;
  border-radius: 50%;
  box-shadow: 0 0 12px rgba(255, 255, 255, 0.8), 0 2px 8px rgba(0,0,0,0.3);
  transition: left var(--transition-smooth);
  transform: translateX(-50%);
}

.stability-scale {
  display: flex;
  justify-content: space-between;
  margin-top: 8px;
  font-size: 10px;
  color: var(--text-muted);
  font-weight: 500;
}

/* Comparison Summary */
.comparison-summary {
  background: var(--bg-card);
}

.comparison-text p {
  font-size: 13px;
  line-height: 1.7;
  color: var(--text-secondary);
  margin-bottom: 12px;
}

.comparison-text p:last-child {
  margin-bottom: 0;
}

.comparison-text .highlight {
  color: var(--board-b);
  font-weight: 600;
}

/* Export Button */
.export-btn {
  width: 100%;
  padding: 16px;
  background: var(--bg-card);
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: 12px;
  color: var(--text-primary);
  font-size: 13px;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition-smooth);
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
}

.export-btn:hover {
  background: var(--bg-glass-light);
  border-color: var(--board-b);
  box-shadow: 0 0 20px var(--board-b-glow);
}

/* ==================== FOOTER ==================== */
.footer {
  padding: 14px 32px;
  background: var(--bg-glass);
  backdrop-filter: blur(var(--blur-amount));
  border-top: var(--border-glass);
  text-align: center;
}

.footer-content {
  font-size: 11px;
  color: var(--text-muted);
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 8px;
}

.footer .divider {
  opacity: 0.3;
}

/* ==================== MODAL ==================== */
.modal {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.85);
  backdrop-filter: blur(8px);
  display: none;
  align-items: center;
  justify-content: center;
  z-index: 1000;
  opacity: 0;
  transition: opacity var(--transition-smooth);
}

.modal.active {
  display: flex;
  opacity: 1;
}

.modal-content {
  background: var(--bg-dark);
  border-radius: 20px;
  width: 90%;
  max-width: 520px;
  max-height: 85vh;
  overflow: hidden;
  position: relative;
  border: var(--border-glass);
  box-shadow: var(--shadow-soft), var(--shadow-glow);
  transform: scale(0.95);
  transition: transform var(--transition-bounce);
}

.modal.active .modal-content {
  transform: scale(1);
}

.modal-close {
  position: absolute;
  top: 18px;
  right: 18px;
  width: 36px;
  height: 36px;
  border: none;
  background: rgba(0, 0, 0, 0.4);
  color: white;
  font-size: 24px;
  border-radius: 50%;
  cursor: pointer;
  z-index: 10;
  transition: all var(--transition-smooth);
  display: flex;
  align-items: center;
  justify-content: center;
}

.modal-close:hover {
  background: rgba(255, 255, 255, 0.2);
  transform: rotate(90deg);
}

.modal-header {
  padding: 32px 28px;
  position: relative;
  overflow: hidden;
}

.modal-header::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 60%;
  background: linear-gradient(transparent, var(--bg-dark));
}

.modal-header h2 {
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 1.5px;
  opacity: 0.7;
  position: relative;
  z-index: 1;
}

.modal-header h3 {
  font-family: 'Space Grotesk', sans-serif;
  font-size: 28px;
  font-weight: 700;
  margin-top: 6px;
  position: relative;
  z-index: 1;
}

.modal-body {
  padding: 24px 28px;
  max-height: 350px;
  overflow-y: auto;
}

.modal-stat {
  display: flex;
  justify-content: space-between;
  padding: 14px 0;
  border-bottom: 1px solid rgba(255, 255, 255, 0.04);
  font-size: 14px;
}

.modal-stat span:first-child {
  color: var(--text-secondary);
}

.modal-stat span:last-child {
  font-weight: 600;
}

.modal-terrain {
  display: flex;
  gap: 8px;
  margin: 18px 0;
  flex-wrap: wrap;
}

.terrain-badge {
  padding: 6px 14px;
  background: var(--bg-glass-light);
  border-radius: 20px;
  font-size: 11px;
  font-weight: 600;
}

.terrain-badge.high {
  background: var(--accent-secondary);
  color: var(--bg-dark);
}

.modal-description {
  margin-top: 18px;
  padding: 18px;
  background: var(--bg-glass);
  border-radius: 12px;
  font-size: 14px;
  line-height: 1.7;
  color: var(--text-secondary);
  border: var(--border-glass);
}

.modal-actions {
  padding: 20px 28px;
  display: flex;
  gap: 12px;
  border-top: var(--border-glass);
}

.modal-btn {
  flex: 1;
  padding: 14px;
  border: none;
  border-radius: 10px;
  font-size: 13px;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition-smooth);
}

.modal-btn.primary {
  background: var(--board-b);
  color: var(--bg-dark);
}

.modal-btn.primary:hover {
  box-shadow: 0 0 25px var(--board-b-glow);
  transform: translateY(-2px);
}

.modal-btn.secondary {
  background: transparent;
  color: var(--text-primary);
  border: 1px solid rgba(255, 255, 255, 0.1);
}

.modal-btn.secondary:hover {
  background: var(--bg-glass-light);
  border-color: var(--board-a);
}

/* ==================== LOADING STATES ==================== */
.loading {
  position: relative;
  pointer-events: none;
}

.loading::after {
  content: '';
  position: absolute;
  inset: 0;
  background: var(--bg-glass);
  display: flex;
  align-items: center;
  justify-content: center;
}

@keyframes pulse {
  0%, 100% { opacity: 0.4; }
  50% { opacity: 1; }
}

/* ==================== AI FEATURES ==================== */
.ai-section {
  background: linear-gradient(135deg, rgba(102, 126, 234, 0.1) 0%, rgba(118, 75, 162, 0.1) 100%);
  border: 1px solid rgba(102, 126, 234, 0.2);
}

.ai-section h3 {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.ai-feature {
  margin-bottom: 16px;
}

.ai-feature:last-child {
  margin-bottom: 0;
}

.ai-feature label {
  display: block;
  font-size: 11px;
  color: var(--text-secondary);
  margin-bottom: 8px;
  font-weight: 500;
}

.ai-btn {
  width: 100%;
  padding: 14px 20px;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  border: none;
  border-radius: 10px;
  color: white;
  font-size: 13px;
  font-weight: 600;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  transition: all var(--transition-smooth);
  position: relative;
  overflow: hidden;
}

.ai-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 0.6s;
}

.ai-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 25px rgba(102, 126, 234, 0.4);
}

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

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

.ai-input-row {
  display: flex;
  gap: 8px;
}

.ai-input-row input {
  flex: 1;
  padding: 10px 12px;
  background: var(--bg-dark);
  border: 1px solid rgba(255, 255, 255, 0.06);
  border-radius: 8px;
  color: var(--text-primary);
  font-size: 12px;
}

.ai-input-row input:focus {
  outline: none;
  border-color: #667eea;
  box-shadow: 0 0 0 3px rgba(102, 126, 234, 0.15);
}

.ai-generate-btn {
  padding: 10px 14px;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  border: none;
  border-radius: 8px;
  color: white;
  font-size: 14px;
  cursor: pointer;
  transition: all var(--transition-smooth);
}

.ai-generate-btn:hover {
  transform: scale(1.05);
  box-shadow: 0 4px 15px rgba(102, 126, 234, 0.4);
}

.ai-presets {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-top: 10px;
}

.preset-btn {
  padding: 6px 10px;
  background: var(--bg-dark);
  border: 1px solid rgba(255, 255, 255, 0.06);
  border-radius: 16px;
  color: var(--text-secondary);
  font-size: 10px;
  cursor: pointer;
  transition: all var(--transition-smooth);
}

.preset-btn:hover {
  border-color: #667eea;
  color: var(--text-primary);
  background: rgba(102, 126, 234, 0.1);
}

.ai-status {
  padding: 12px;
  background: var(--bg-dark);
  border-radius: 8px;
  margin-top: 12px;
}

.ai-loading {
  display: flex;
  align-items: center;
  gap: 12px;
  color: var(--text-secondary);
  font-size: 12px;
}

.spinner {
  width: 18px;
  height: 18px;
  border: 2px solid rgba(102, 126, 234, 0.2);
  border-top-color: #667eea;
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

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

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

/* AI Advice Panel */
.ai-advice-panel {
  background: var(--bg-card);
  border-radius: 12px;
  padding: 16px;
  margin-top: 12px;
  border: 1px solid rgba(102, 126, 234, 0.2);
}

.advice-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 12px;
}

.advice-badge {
  padding: 6px 14px;
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  border-radius: 20px;
  font-size: 12px;
  font-weight: 700;
  color: white;
}

.advice-badge.board-a {
  background: linear-gradient(135deg, var(--board-a) 0%, #ff8585 100%);
}

.advice-badge.board-b {
  background: linear-gradient(135deg, var(--board-b) 0%, #6dd5c7 100%);
}

.advice-confidence {
  font-size: 11px;
  color: var(--text-muted);
}

.advice-summary {
  font-size: 14px;
  line-height: 1.6;
  color: var(--text-primary);
  margin-bottom: 16px;
  padding-bottom: 16px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.04);
}

.advice-comparison {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
  margin-bottom: 16px;
}

.advice-board h4 {
  font-size: 11px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  margin-bottom: 8px;
}

.advice-pros, .advice-cons {
  font-size: 11px;
  line-height: 1.6;
}

.advice-pros span {
  color: var(--accent-secondary);
}

.advice-cons span {
  color: var(--accent-danger);
}

.advice-pros div, .advice-cons div {
  padding: 2px 0;
  color: var(--text-secondary);
}

.advice-tips {
  background: var(--bg-dark);
  border-radius: 8px;
  padding: 12px;
}

.advice-tips h5 {
  font-size: 10px;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  color: var(--text-muted);
  margin-bottom: 8px;
}

.advice-tips ul {
  margin: 0;
  padding-left: 16px;
}

.advice-tips li {
  font-size: 11px;
  color: var(--text-secondary);
  padding: 2px 0;
}

.advice-warning {
  margin-top: 12px;
  padding: 12px;
  background: rgba(248, 81, 73, 0.1);
  border: 1px solid rgba(248, 81, 73, 0.2);
  border-radius: 8px;
  font-size: 11px;
  color: var(--accent-danger);
}

/* ==================== RESPONSIVE ==================== */
@media (max-width: 1200px) {
  .main-container {
    grid-template-columns: 280px 1fr 300px;
  }
}

@media (max-width: 1024px) {
  .main-container {
    grid-template-columns: 1fr;
    grid-template-rows: auto 1fr auto;
  }
  
  .panel {
    max-height: none;
    border: none !important;
    border-bottom: var(--border-glass) !important;
  }
  
  .right-panel {
    border-bottom: none !important;
  }
  
  .board-selectors {
    flex-direction: column;
    gap: 20px;
  }
}

@media (max-width: 640px) {
  .header {
    flex-direction: column;
    gap: 12px;
    padding: 12px 16px;
  }
  
  .logo h1 {
    font-size: 18px;
  }
  
  .skill-toggle {
    width: 100%;
    justify-content: center;
  }
  
  .skill-btn {
    padding: 8px 14px;
    font-size: 12px;
  }
  
  .viz-toggles {
    flex-wrap: wrap;
    gap: 12px;
  }
  
  /* Hide left panel (profile) on mobile - use modal instead */
  .left-panel {
    display: none;
  }
  
  /* Mobile board details - simplified */
  .right-panel {
    padding: 12px;
  }
  
  .right-panel .board-detail {
    margin-bottom: 10px;
  }
  
  .board-stats {
    padding: 12px;
  }
  
  .stat-row {
    padding: 6px 0;
  }
  
  /* Hide stability indicator on mobile to save space */
  .stability-indicator {
    display: none;
  }
  
  /* Simplified simulator controls on mobile */
  .simulator-controls {
    padding: 12px 16px;
  }
  
  .board-selectors {
    gap: 12px;
    margin-bottom: 12px;
  }
  
  .board-label {
    font-size: 10px;
  }
  
  .slider-value {
    font-size: 13px;
    min-width: 55px;
  }
  
  /* Scenario buttons - smaller on mobile */
  .scenario-selector {
    gap: 6px;
    margin-bottom: 10px;
  }
  
  .scenario-btn {
    padding: 5px 10px;
    font-size: 10px;
  }
  
  .replay-btn {
    padding: 5px 10px;
    font-size: 10px;
  }
  
  /* Terrain buttons - smaller */
  .terrain-selector {
    gap: 8px;
    margin-bottom: 10px;
  }
  
  .terrain-btn {
    padding: 6px 12px;
    font-size: 11px;
  }
  
  /* Canvas container - reduce min-height on mobile */
  #canvas-container {
    min-height: 300px;
  }
  
  /* Footer - smaller */
  .footer {
    padding: 10px 16px;
  }
  
  .footer-content {
    font-size: 10px;
    flex-wrap: wrap;
  }
}

/* Extra small screens */
@media (max-width: 480px) {
  .header {
    padding: 10px 12px;
  }
  
  .logo-icon {
    font-size: 24px;
  }
  
  .logo h1 {
    font-size: 16px;
  }
  
  .skill-btn {
    padding: 6px 12px;
    font-size: 11px;
  }
  
  /* Stack scenario buttons in rows */
  .scenario-selector {
    flex-wrap: wrap;
    justify-content: center;
  }
  
  .scenario-selector > span {
    width: 100%;
    text-align: center;
    margin-bottom: 4px;
  }
  
  .terrain-selector {
    flex-wrap: wrap;
    justify-content: center;
  }
  
  .terrain-selector > span {
    width: 100%;
    text-align: center;
    margin-bottom: 4px;
  }
  
  /* Board detail cards - even more compact */
  .board-header {
    padding: 12px 14px;
  }
  
  .board-name {
    font-size: 12px;
  }
  
  .stat-value {
    font-size: 12px;
  }
  
  .stat-label {
    font-size: 11px;
  }
  
  /* Hide comparison summary on very small screens */
  .comparison-summary {
    display: none;
  }
}