/* =============================================================================
 * DeepCFR / CFR+ 算法演示 - 样式表
 *
 * 设计理念：克制的技术演示界面 + 原生 SVG 图表 + 响应式交互
 * 配色：深蓝底 + 青蓝/紫粉渐变强调
 * =============================================================================
 */

/* ==================== CSS 变量 ==================== */
:root {
  --bg-primary: #0a0e27;
  --bg-secondary: #131831;
  --bg-tertiary: #1a2046;
  --bg-card: rgba(26, 32, 70, 0.78);
  --bg-glass: rgba(255, 255, 255, 0.08);

  --accent-cyan: #00d4ff;
  --accent-pink: #ff6b9d;
  --accent-purple: #8b5cf6;
  --accent-green: #10b981;
  --accent-yellow: #fbbf24;

  --text-primary: #e4e9f0;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;

  --border-color: rgba(255, 255, 255, 0.1);
  --border-hover: rgba(0, 212, 255, 0.45);

  --shadow-glow: 0 0 24px rgba(0, 212, 255, 0.32);
  --shadow-pink: 0 0 24px rgba(255, 107, 157, 0.26);
  --shadow-card: 0 10px 30px rgba(0, 0, 0, 0.36);

  --gradient-primary: linear-gradient(135deg, var(--accent-cyan) 0%, var(--accent-purple) 100%);
  --gradient-secondary: linear-gradient(135deg, var(--accent-pink) 0%, var(--accent-purple) 100%);
  --gradient-bg: linear-gradient(135deg, #0a0e27 0%, #0f2744 48%, #1b103d 100%);

  --container-width: 1200px;
  --border-radius: 8px;
  --border-radius-lg: 8px;

  --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 0.6s cubic-bezier(0.4, 0, 0.2, 1);
}

body.light {
  --bg-primary: #f8fbff;
  --bg-secondary: #eef5ff;
  --bg-tertiary: #dfeaff;
  --bg-card: rgba(255, 255, 255, 0.88);
  --bg-glass: rgba(10, 14, 39, 0.05);
  --text-primary: #14213f;
  --text-secondary: #475569;
  --text-muted: #718096;
  --border-color: rgba(10, 14, 39, 0.12);
  --border-hover: rgba(0, 148, 204, 0.42);
  --gradient-bg: linear-gradient(135deg, #f8fbff 0%, #edf7ff 52%, #f7efff 100%);
}

/* ==================== Reset & Base ==================== */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
               "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  background: var(--gradient-bg);
  color: var(--text-primary);
  line-height: 1.6;
  min-height: 100vh;
  overflow-x: hidden;
}

/* 背景网格 */
body::before {
  content: '';
  position: fixed;
  inset: 0;
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.045) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.045) 1px, transparent 1px);
  background-size: 48px 48px;
  mask-image: linear-gradient(to bottom, rgba(0, 0, 0, 0.8), transparent 78%);
  pointer-events: none;
  z-index: -1;
}

a {
  color: var(--accent-cyan);
  text-decoration: none;
  transition: color var(--transition);
}

a:hover {
  color: var(--accent-pink);
}

/* ==================== Header / Navigation ==================== */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: rgba(10, 14, 39, 0.88);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border-color);
}

.nav-container {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: 1rem 2rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-weight: 700;
  font-size: 1.25rem;
}

.logo-icon {
  font-size: 1.5rem;
  filter: drop-shadow(0 0 10px var(--accent-cyan));
}

.logo-text {
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.nav-links {
  display: flex;
  list-style: none;
  gap: 2rem;
}

.nav-links a {
  color: var(--text-secondary);
  font-weight: 500;
  transition: color var(--transition);
  position: relative;
}

.nav-links a:hover {
  color: var(--accent-cyan);
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--accent-cyan);
  transition: width var(--transition);
}

.nav-links a:hover::after {
  width: 100%;
}

.theme-toggle {
  background: var(--bg-glass);
  border: 1px solid var(--border-color);
  color: var(--text-primary);
  width: 40px;
  height: 40px;
  border-radius: 50%;
  cursor: pointer;
  font-size: 1.25rem;
  transition: all var(--transition);
}

.theme-toggle:hover {
  border-color: var(--accent-cyan);
  box-shadow: var(--shadow-glow);
}

body.light .site-header {
  background: rgba(248, 251, 255, 0.9);
}

/* ==================== Hero Section ==================== */
.hero-section {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 8rem 2rem 4rem;
  overflow: hidden;
}

.hero-bg {
  position: absolute;
  inset: 0;
  background:
    linear-gradient(135deg, rgba(0, 212, 255, 0.16), transparent 45%),
    linear-gradient(45deg, transparent 35%, rgba(139, 92, 246, 0.16));
  opacity: 0.9;
}

.hero-content {
  max-width: 900px;
  text-align: center;
  position: relative;
  z-index: 1;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.5rem 1rem;
  background: var(--bg-glass);
  border: 1px solid var(--border-color);
  border-radius: 100px;
  font-size: 0.875rem;
  color: var(--text-secondary);
  margin-bottom: 2rem;
}

.badge-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--accent-green);
  animation: dotBlink 2s ease-in-out infinite;
}

@keyframes dotBlink {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.3; }
}

.hero-title {
  font-size: clamp(2.5rem, 6vw, 4.5rem);
  font-weight: 800;
  line-height: 1.1;
  margin-bottom: 1.5rem;
}

.gradient-text {
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  position: relative;
}

.hero-subtitle {
  font-size: 1.125rem;
  color: var(--text-secondary);
  max-width: 680px;
  margin: 0 auto 1rem;
  line-height: 1.7;
}

.hero-note {
  max-width: 720px;
  margin: 0 auto 2.5rem;
  color: var(--text-muted);
  font-size: 0.95rem;
  line-height: 1.7;
}

.hero-actions {
  display: flex;
  gap: 1rem;
  justify-content: center;
  margin-bottom: 4rem;
  flex-wrap: wrap;
}

.hero-stats {
  display: flex;
  gap: 3rem;
  justify-content: center;
  flex-wrap: wrap;
}

.stat-item {
  text-align: center;
}

.stat-value {
  display: block;
  font-size: 2.5rem;
  font-weight: 700;
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.stat-label {
  font-size: 0.875rem;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0;
}

/* ==================== Buttons ==================== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.875rem 1.75rem;
  border-radius: var(--border-radius);
  font-weight: 600;
  font-size: 1rem;
  cursor: pointer;
  transition: all var(--transition);
  border: none;
  text-decoration: none;
  white-space: nowrap;
}

.btn-primary {
  background: var(--gradient-primary);
  color: white;
  box-shadow: var(--shadow-glow);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 0 40px rgba(0, 212, 255, 0.5);
}

.btn-secondary {
  background: var(--bg-glass);
  color: var(--text-primary);
  border: 1px solid var(--border-color);
  backdrop-filter: blur(10px);
}

.btn-secondary:hover {
  border-color: var(--accent-cyan);
  background: rgba(0, 212, 255, 0.1);
}

.btn-play, .btn-reset {
  padding: 0.625rem 1.25rem;
  font-size: 0.875rem;
}

/* ==================== Sections ==================== */
.section {
  padding: 6rem 2rem;
}

.section-alt {
  background: rgba(255, 255, 255, 0.02);
}

.container {
  max-width: var(--container-width);
  margin: 0 auto;
}

.section-header {
  text-align: center;
  margin-bottom: 4rem;
}

.section-tag {
  display: inline-block;
  padding: 0.375rem 1rem;
  background: var(--bg-glass);
  border: 1px solid var(--border-color);
  border-radius: 100px;
  font-size: 0.75rem;
  font-weight: 600;
  color: var(--accent-cyan);
  text-transform: uppercase;
  letter-spacing: 0;
  margin-bottom: 1rem;
}

.section-title {
  font-size: clamp(2rem, 4vw, 3rem);
  font-weight: 700;
  margin-bottom: 1rem;
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

.section-desc {
  font-size: 1.125rem;
  color: var(--text-secondary);
  max-width: 600px;
  margin: 0 auto;
}

/* ==================== Algorithm Timeline ==================== */
.algorithm-timeline {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 1.5rem;
  margin-bottom: 4rem;
}

.timeline-card {
  background: var(--bg-card);
  backdrop-filter: blur(10px);
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius);
  padding: 1.5rem;
  transition: all var(--transition);
  position: relative;
  overflow: hidden;
}

.timeline-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 4px;
  height: 100%;
  background: var(--gradient-primary);
  opacity: 0;
  transition: opacity var(--transition);
}

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

.timeline-card:hover::before {
  opacity: 1;
}

.timeline-card.highlight {
  border-color: var(--accent-pink);
}

.timeline-year {
  display: inline-block;
  font-size: 0.875rem;
  font-weight: 700;
  color: var(--accent-cyan);
  margin-bottom: 0.75rem;
  padding: 0.25rem 0.75rem;
  background: rgba(0, 212, 255, 0.1);
  border-radius: 100px;
}

.timeline-card h3 {
  font-size: 1.25rem;
  margin-bottom: 0.5rem;
  color: var(--text-primary);
}

.timeline-card p {
  color: var(--text-secondary);
  font-size: 0.875rem;
}

/* ==================== Formula Block ==================== */
.formula-block {
  background: var(--bg-card);
  backdrop-filter: blur(10px);
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius-lg);
  padding: 2.5rem;
}

.formula-block h3 {
  font-size: 1.5rem;
  margin-bottom: 1.5rem;
  color: var(--accent-cyan);
}

.formula-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
}

.formula-item {
  padding: 1.25rem;
  background: rgba(0, 0, 0, 0.3);
  border-radius: var(--border-radius);
  border: 1px solid var(--border-color);
}

.formula-label {
  font-size: 0.75rem;
  color: var(--accent-cyan);
  text-transform: uppercase;
  letter-spacing: 0;
  margin-bottom: 0.5rem;
  font-weight: 600;
}

.formula-math {
  font-family: 'Times New Roman', serif;
  font-size: 1.125rem;
  color: var(--text-primary);
  font-style: italic;
}

/* ==================== Game Rules ==================== */
.game-rules {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 1.5rem;
  margin-bottom: 4rem;
}

.rule-card {
  background: var(--bg-card);
  backdrop-filter: blur(10px);
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius);
  padding: 1.5rem;
  transition: all var(--transition);
  position: relative;
}

.rule-card:hover {
  border-color: var(--accent-purple);
  transform: translateY(-4px);
}

.rule-number {
  display: inline-block;
  font-size: 2rem;
  font-weight: 800;
  background: var(--gradient-secondary);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  margin-bottom: 0.5rem;
}

.rule-card h3 {
  font-size: 1.125rem;
  margin-bottom: 0.75rem;
  color: var(--text-primary);
}

.rule-card p {
  color: var(--text-secondary);
  font-size: 0.875rem;
  line-height: 1.6;
}

.rule-card strong {
  color: var(--accent-cyan);
}

/* ==================== Payoff Table ==================== */
.payoff-table-wrapper {
  background: var(--bg-card);
  backdrop-filter: blur(10px);
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius-lg);
  padding: 2.5rem;
}

.payoff-table-wrapper h3 {
  font-size: 1.25rem;
  margin-bottom: 1.5rem;
  color: var(--accent-cyan);
}

.payoff-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.95rem;
}

.payoff-table th,
.payoff-table td {
  padding: 1rem;
  text-align: center;
  border: 1px solid var(--border-color);
}

.payoff-table thead th {
  background: rgba(0, 212, 255, 0.1);
  color: var(--accent-cyan);
  font-weight: 600;
}

.payoff-table tbody td:first-child {
  background: rgba(0, 212, 255, 0.05);
  font-weight: 700;
  color: var(--accent-cyan);
}

.payoff-table .positive {
  color: var(--accent-green);
  font-weight: 600;
}

.payoff-table .negative {
  color: var(--accent-pink);
  font-weight: 600;
}

.payoff-table .neutral {
  color: var(--text-muted);
}

.payoff-note {
  margin-top: 1rem;
  text-align: center;
  color: var(--text-muted);
  font-size: 0.875rem;
  font-style: italic;
}

/* ==================== Visualization Cards ==================== */
.viz-card {
  background: var(--bg-card);
  backdrop-filter: blur(10px);
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius-lg);
  padding: 2rem;
  margin-bottom: 2rem;
  transition: border-color var(--transition);
}

.viz-card:hover {
  border-color: var(--border-hover);
}

.viz-card h3 {
  font-size: 1.5rem;
  margin-bottom: 0.5rem;
  color: var(--text-primary);
}

.viz-desc {
  color: var(--text-secondary);
  font-size: 0.95rem;
  margin-bottom: 1.5rem;
}

.viz-container {
  background: rgba(0, 0, 0, 0.3);
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius);
  padding: 1.5rem;
  min-height: 300px;
  margin-bottom: 1.5rem;
  overflow-x: auto;
}

.viz-controls {
  display: flex;
  gap: 1rem;
  align-items: center;
  flex-wrap: wrap;
}

.slider-label {
  display: flex;
  align-items: center;
  gap: 1rem;
  color: var(--text-secondary);
  font-size: 0.875rem;
  flex: 1;
  min-width: 300px;
}

.slider-label input[type="range"] {
  flex: 1;
  accent-color: var(--accent-cyan);
}

#iteration-value {
  font-weight: 600;
  color: var(--accent-cyan);
  min-width: 60px;
  text-align: right;
}

/* ==================== Playground ==================== */
.playground {
  max-width: 900px;
  margin: 0 auto;
}

.game-board {
  display: grid;
  gap: 1.5rem;
}

.player-panel,
.action-panel,
.result-panel {
  background: var(--bg-card);
  backdrop-filter: blur(10px);
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius-lg);
  padding: 2rem;
}

.player-panel h3,
.action-panel h3,
.result-panel h3 {
  font-size: 1.25rem;
  margin-bottom: 1rem;
  color: var(--accent-cyan);
}

.card-selector {
  display: flex;
  gap: 1rem;
  margin-bottom: 1.5rem;
  flex-wrap: wrap;
}

.card-btn {
  flex: 1;
  min-width: 100px;
  padding: 1.5rem 1rem;
  background: var(--bg-glass);
  border: 2px solid var(--border-color);
  border-radius: var(--border-radius);
  color: var(--text-primary);
  cursor: pointer;
  transition: all var(--transition);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.5rem;
}

.card-btn:hover {
  border-color: var(--accent-cyan);
  transform: translateY(-2px);
  box-shadow: var(--shadow-glow);
}

.card-btn.selected {
  border-color: var(--accent-cyan);
  background: rgba(0, 212, 255, 0.1);
}

.card-btn[data-card="H"]:hover { border-color: var(--accent-green); }
.card-btn[data-card="M"]:hover { border-color: var(--accent-yellow); }
.card-btn[data-card="L"]:hover { border-color: var(--accent-pink); }

.card-rank {
  font-size: 2.5rem;
  font-weight: 800;
}

.card-btn[data-card="H"] .card-rank { color: var(--accent-green); }
.card-btn[data-card="M"] .card-rank { color: var(--accent-yellow); }
.card-btn[data-card="L"] .card-rank { color: var(--accent-pink); }

.card-label {
  font-size: 0.875rem;
  color: var(--text-secondary);
}

.opponent-info {
  padding: 1rem;
  background: rgba(0, 0, 0, 0.3);
  border-radius: var(--border-radius);
  color: var(--text-secondary);
  text-align: center;
}

#opponent-card {
  font-weight: 700;
  color: var(--accent-pink);
}

.action-display {
  padding: 1.5rem;
  background: rgba(0, 0, 0, 0.3);
  border-radius: var(--border-radius);
  margin-bottom: 1.5rem;
  text-align: center;
  color: var(--text-secondary);
}

.action-buttons {
  display: flex;
  gap: 1rem;
}

.action-btn {
  flex: 1;
  padding: 1.25rem;
  background: var(--bg-glass);
  border: 2px solid var(--border-color);
  border-radius: var(--border-radius);
  color: var(--text-primary);
  cursor: pointer;
  transition: all var(--transition);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.5rem;
  font-size: 1rem;
  font-weight: 600;
}

.action-btn:hover {
  border-color: var(--accent-cyan);
  background: rgba(0, 212, 255, 0.1);
  transform: translateY(-2px);
}

.action-icon {
  font-size: 1.5rem;
}

.action-btn:disabled {
  cursor: wait;
  opacity: 0.62;
  transform: none;
}

.decision-meta,
.strategy-hint,
.ai-thinking,
.ai-action {
  margin-top: 0.5rem;
  color: var(--text-secondary);
  font-size: 0.9rem;
}

.decision-meta span,
.strategy-hint {
  color: var(--accent-cyan);
}

.ai-thinking,
.ai-action {
  color: var(--accent-yellow);
}

.result-summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 1rem;
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius);
  background: rgba(0, 0, 0, 0.22);
  margin-bottom: 1rem;
}

.result-title {
  font-size: 1.35rem;
  font-weight: 800;
}

.result-payoff {
  font-weight: 700;
}

.result-win { color: var(--accent-green); }
.result-loss { color: var(--accent-pink); }
.result-draw { color: var(--accent-yellow); }

.result-details {
  display: grid;
  gap: 0.75rem;
  margin-bottom: 1.25rem;
}

.result-details div {
  display: grid;
  grid-template-columns: 90px 1fr;
  gap: 1rem;
  align-items: baseline;
}

.result-details dt {
  color: var(--text-muted);
}

.result-details dd {
  color: var(--text-primary);
  font-weight: 600;
}

/* ==================== Native SVG Charts ==================== */
.viz-svg {
  display: block;
  width: 100%;
  height: auto;
  min-width: 620px;
}

.tree-link,
.tree-edge-label,
.tree-node {
  opacity: 0;
  transition: opacity 0.45s ease, transform 0.45s ease;
}

.tree-link.is-visible,
.tree-edge-label.is-visible,
.tree-node.is-visible {
  opacity: 1;
}

.tree-link {
  fill: none;
  stroke: rgba(255, 255, 255, 0.24);
  stroke-width: 2;
}

body.light .tree-link {
  stroke: rgba(16, 18, 22, 0.24);
}

.tree-edge-label,
.tree-legend text,
.chart-axis-label,
.chart-tick,
.heatmap-label {
  fill: var(--text-secondary);
  font-size: 13px;
}

.tree-node circle {
  stroke: rgba(255, 255, 255, 0.26);
  stroke-width: 2;
}

.tree-node-p1 circle,
circle.tree-node-p1 {
  fill: var(--accent-cyan);
}

.tree-node-p2 circle,
circle.tree-node-p2 {
  fill: var(--accent-pink);
}

.tree-node-terminal circle,
circle.tree-node-terminal {
  fill: var(--accent-yellow);
}

.tree-node-label {
  fill: #0a0e27;
  font-size: 13px;
  font-weight: 800;
}

.tree-node-sub {
  fill: var(--text-secondary);
  font-size: 12px;
}

.chart-title {
  fill: var(--text-primary);
  font-size: 16px;
  font-weight: 700;
}

.heatmap-col {
  font-size: 13px;
  font-weight: 700;
}

.heatmap-pass { fill: var(--accent-cyan); }
.heatmap-bet { fill: var(--accent-pink); }

.heatmap-cell {
  stroke: var(--border-color);
  stroke-width: 1;
}

.heatmap-cell-group:hover .heatmap-cell {
  stroke: var(--text-primary);
  stroke-width: 2;
}

.heatmap-value {
  fill: var(--text-primary);
  font-size: 12px;
  font-weight: 700;
  pointer-events: none;
}

.heatmap-value-strong {
  fill: #0a0e27;
}

.chart-grid {
  stroke: var(--border-color);
  stroke-width: 1;
}

.chart-grid-vertical {
  opacity: 0.55;
}

.chart-axis {
  stroke: var(--text-muted);
  stroke-width: 1.25;
}

.chart-area {
  fill: url(#strategy-line-gradient);
  opacity: 0.16;
}

.chart-line {
  fill: none;
  stroke: url(#strategy-line-gradient);
  stroke-width: 3;
  stroke-linejoin: round;
  stroke-linecap: round;
}

.chart-marker circle {
  fill: var(--bg-primary);
  stroke: var(--accent-yellow);
  stroke-width: 2;
}

.chart-marker text {
  fill: var(--text-secondary);
  font-size: 12px;
}

.viz-error {
  padding: 2rem;
  text-align: center;
  color: var(--accent-pink);
}

/* ==================== Notes ==================== */
.notes-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
}

.note-card {
  background: var(--bg-card);
  backdrop-filter: blur(10px);
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius);
  padding: 1.5rem;
  transition: all var(--transition);
}

.note-card:hover {
  border-color: var(--accent-purple);
  transform: translateY(-4px);
}

.note-card h3 {
  font-size: 1.25rem;
  margin-bottom: 0.75rem;
  color: var(--text-primary);
}

.note-card p {
  color: var(--text-secondary);
  font-size: 0.95rem;
  margin-bottom: 1rem;
  line-height: 1.6;
}

.note-link {
  display: inline-block;
  color: var(--accent-cyan);
  font-weight: 600;
  font-size: 0.875rem;
  transition: color var(--transition);
}

.note-link:hover {
  color: var(--accent-pink);
}

/* ==================== Content Pages ==================== */
.content-page {
  padding: 9rem 2rem 5rem;
  min-height: 100vh;
}

.prose {
  max-width: 820px;
  background: var(--bg-card);
  border: 1px solid var(--border-color);
  border-radius: var(--border-radius);
  padding: 2.5rem;
  box-shadow: var(--shadow-card);
}

.prose h1 {
  font-size: clamp(2rem, 4vw, 3rem);
  line-height: 1.15;
  margin: 0 0 1.5rem;
  color: var(--text-primary);
}

.prose h2 {
  font-size: 1.35rem;
  margin: 2rem 0 0.75rem;
  color: var(--accent-cyan);
}

.prose p {
  margin: 0 0 1rem;
  color: var(--text-secondary);
}

.muted-note {
  color: var(--text-muted);
  font-size: 0.9rem;
}

/* ==================== Ad Section ==================== */
.ad-section {
  padding: 2rem;
  text-align: center;
}

.ad-placeholder {
  max-width: 728px;
  height: 90px;
  margin: 0 auto;
  background: var(--bg-card);
  border: 1px dashed var(--border-color);
  border-radius: var(--border-radius);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-muted);
  font-size: 0.875rem;
}

/* ==================== Footer ==================== */
.site-footer {
  background: rgba(0, 0, 0, 0.4);
  border-top: 1px solid var(--border-color);
  padding: 3rem 2rem 2rem;
  margin-top: 4rem;
}

.footer-content {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 2rem;
  margin-bottom: 2rem;
}

.footer-section h4 {
  color: var(--accent-cyan);
  font-size: 1rem;
  margin-bottom: 0.75rem;
}

.footer-section p {
  color: var(--text-secondary);
  font-size: 0.875rem;
  line-height: 1.6;
}

.footer-bottom {
  text-align: center;
  padding-top: 2rem;
  border-top: 1px solid var(--border-color);
  color: var(--text-muted);
  font-size: 0.875rem;
}

.footer-bottom .footer-beian {
  
}

.footer-bottom .footer-beian a {
  display: inline-flex;
  align-items: center;
  gap: 0.375rem;
}

.footer-bottom .footer-beian img {
  width: 18px;
  height: 20px;
}

/* ==================== Responsive ==================== */
@media (max-width: 768px) {
  .nav-container {
    padding: 0.75rem 1rem;
    gap: 0.75rem;
    flex-wrap: wrap;
  }

  .nav-links {
    order: 3;
    width: 100%;
    display: flex;
    gap: 1rem;
    overflow-x: auto;
    padding-bottom: 0.15rem;
    scrollbar-width: none;
  }

  .nav-links::-webkit-scrollbar {
    display: none;
  }

  .nav-links a {
    font-size: 0.875rem;
    white-space: nowrap;
  }

  .hero-section {
    padding-top: 9.5rem;
  }

  .hero-stats {
    gap: 1.5rem;
  }

  .stat-value {
    font-size: 2rem;
  }

  .section {
    padding: 4rem 1.5rem;
  }

  .formula-block,
  .payoff-table-wrapper,
  .viz-card,
  .player-panel,
  .action-panel,
  .result-panel {
    padding: 1.25rem;
  }

  .viz-container {
    min-height: 220px;
    padding: 1rem;
  }

  .viz-svg {
    min-width: 560px;
  }

  .card-btn {
    min-width: 80px;
    padding: 1rem 0.5rem;
  }

  .card-rank {
    font-size: 2rem;
  }

  .result-summary,
  .result-details div {
    grid-template-columns: 1fr;
  }

  .result-summary {
    align-items: flex-start;
    flex-direction: column;
  }
}

/* ==================== Animations ==================== */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.section-header,
.viz-card,
.rule-card,
.timeline-card {
  animation: fadeInUp 0.6s ease-out backwards;
}

.section-header { animation-delay: 0.1s; }
.viz-card:nth-child(2) { animation-delay: 0.2s; }
.viz-card:nth-child(3) { animation-delay: 0.3s; }
.viz-card:nth-child(4) { animation-delay: 0.4s; }

/* ==================== SVG/D3 自定义样式 ==================== */
.node circle {
  cursor: pointer;
  transition: r 0.3s ease, fill 0.3s ease;
}

.node circle:hover {
  r: 12;
}

.link {
  fill: none;
  stroke: rgba(255, 255, 255, 0.2);
  stroke-width: 1.5;
  transition: stroke 0.3s ease;
}

.link.active {
  stroke: var(--accent-cyan);
  stroke-width: 2.5;
  filter: drop-shadow(0 0 8px var(--accent-cyan));
}

.heatmap-cell {
  transition: opacity 0.3s ease;
  cursor: pointer;
}

.heatmap-cell:hover {
  opacity: 0.8;
  stroke: var(--accent-cyan);
  stroke-width: 2;
}

.axis text {
  fill: var(--text-secondary);
  font-size: 12px;
}

.axis path,
.axis line {
  stroke: var(--border-color);
}

.grid line {
  stroke: var(--border-color);
  stroke-opacity: 0.3;
}