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

:root {
  /* 颜色主题 */
  --primary-dark: #1a1a2e;
  --secondary-dark: #16213e;
  --accent-gold: #d4af37;
  --text-light: #eaeaea;
  --text-muted: #999999;
  --border-color: #333333;
  --success-color: #4ade80;
  --error-color: #ef4444;

  /* 棋盘颜色 */
  --board-bg: #c9a961;
  --board-line: #4a4a4a;
  --black-stone: #1a1a1a;
  --white-stone: #f5f5f5;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
  background-color: var(--primary-dark);
  color: var(--text-light);
  line-height: 1.6;
  overflow-x: hidden;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

/* 导航栏 */
.navbar {
  background: var(--secondary-dark);
  border-bottom: 2px solid var(--accent-gold);
  position: sticky;
  top: 0;
  z-index: 1000;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.3);
}

.navbar .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 15px 20px;
}

.nav-brand h1 {
  font-size: 24px;
  color: var(--accent-gold);
  letter-spacing: 2px;
}

.nav-brand a {
  text-decoration: none;
  color: var(--accent-gold);
}

.nav-menu {
  display: flex;
  list-style: none;
  gap: 30px;
}

.nav-link {
  text-decoration: none;
  color: var(--text-light);
  font-weight: 500;
  transition: color 0.3s;
  position: relative;
}

.nav-link:hover,
.nav-link.active {
  color: var(--accent-gold);
}

.nav-link.active::after {
  content: "";
  position: absolute;
  bottom: -5px;
  left: 0;
  width: 100%;
  height: 2px;
  background: var(--accent-gold);
}

/* 按钮样式 */
.btn {
  padding: 12px 28px;
  border: none;
  border-radius: 6px;
  font-size: 16px;
  font-weight: 600;
  cursor: pointer;
  transition: all 0.3s;
  text-decoration: none;
  display: inline-block;
}

.btn-primary {
  background: var(--accent-gold);
  color: var(--primary-dark);
}

.btn-primary:hover {
  background: #e6c746;
  transform: translateY(-2px);
  box-shadow: 0 5px 15px rgba(212, 175, 55, 0.3);
}

.btn-secondary {
  background: transparent;
  color: var(--accent-gold);
  border: 2px solid var(--accent-gold);
}

.btn-secondary:hover {
  background: var(--accent-gold);
  color: var(--primary-dark);
}

/* 英雄区 */
.hero {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 60px;
  padding: 100px 0;
  background: linear-gradient(135deg, var(--secondary-dark) 0%, var(--primary-dark) 100%);
}

.hero-content {
  flex: 1;
}

.hero h2 {
  font-size: 48px;
  margin-bottom: 20px;
  color: var(--accent-gold);
  text-shadow: 0 2px 10px rgba(0, 0, 0, 0.5);
}

.hero p {
  font-size: 18px;
  margin-bottom: 30px;
  color: var(--text-light);
  line-height: 1.8;
}

.hero-board {
  flex: 1;
  display: flex;
  justify-content: center;
}

.hero-board canvas {
  border: 3px solid var(--accent-gold);
  border-radius: 8px;
  background: var(--board-bg);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
}

/* 特性区 */
.features {
  padding: 80px 0;
  background: var(--primary-dark);
}

.features h2 {
  text-align: center;
  font-size: 36px;
  margin-bottom: 60px;
  color: var(--accent-gold);
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 30px;
}

.feature-card {
  background: var(--secondary-dark);
  padding: 30px;
  border-radius: 8px;
  border: 1px solid var(--border-color);
  text-align: center;
  transition: all 0.3s;
}

.feature-card:hover {
  border-color: var(--accent-gold);
  transform: translateY(-5px);
  box-shadow: 0 10px 25px rgba(212, 175, 55, 0.1);
}

.feature-icon {
  font-size: 48px;
  margin-bottom: 15px;
}

.feature-card h3 {
  margin-bottom: 15px;
  color: var(--accent-gold);
}

.feature-card p {
  color: var(--text-muted);
  line-height: 1.6;
}

/* 介绍区 */
.intro {
  padding: 80px 0;
  background: linear-gradient(135deg, var(--primary-dark) 0%, var(--secondary-dark) 100%);
  border-top: 2px solid var(--accent-gold);
  border-bottom: 2px solid var(--accent-gold);
}

.intro h2 {
  text-align: center;
  font-size: 36px;
  margin-bottom: 60px;
  color: var(--accent-gold);
}

.intro-content {
  display: flex;
  gap: 60px;
  align-items: center;
}

.intro-text {
  flex: 1;
}

.intro-text p {
  margin-bottom: 20px;
  line-height: 1.8;
  color: var(--text-light);
}

.intro-board {
  flex: 1;
  display: flex;
  justify-content: center;
}

.intro-board canvas {
  border: 3px solid var(--accent-gold);
  border-radius: 8px;
  background: var(--board-bg);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
}

/* 页脚 */
.footer {
  background: var(--secondary-dark);
  border-top: 2px solid var(--accent-gold);
  padding: 60px 0 20px;
  color: var(--text-muted);
}

.footer-content {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 40px;
  margin-bottom: 40px;
}

.footer-section h3,
.footer-section h4 {
  color: var(--accent-gold);
  margin-bottom: 15px;
}

.footer-section ul {
  list-style: none;
}

.footer-section li {
  margin-bottom: 10px;
}

.footer-section a {
  color: var(--text-muted);
  text-decoration: none;
  transition: color 0.3s;
}

.footer-section a:hover {
  color: var(--accent-gold);
}

.footer-bottom {
  text-align: center;
  border-top: 1px solid var(--border-color);
  padding-top: 20px;
}

/* 游戏页面 */
.game-container {
  min-height: calc(100vh - 80px);
  padding: 40px 20px;
}

.game-wrapper {
  max-width: 1200px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1fr 350px;
  gap: 40px;
}

.game-board-section h2 {
  margin-bottom: 20px;
  color: var(--accent-gold);
  text-align: center;
}

.game-canvas {
  display: block;
  margin: 0 auto;
  border: 3px solid var(--accent-gold);
  border-radius: 8px;
  background: var(--board-bg);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
  cursor: crosshair;
}

.game-info {
  margin-top: 20px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 15px;
  background: var(--secondary-dark);
  border-radius: 6px;
  border: 1px solid var(--border-color);
}

.player-info {
  display: flex;
  align-items: center;
  gap: 10px;
}

.player-label {
  color: var(--text-muted);
}

.player-marker {
  font-size: 20px;
  font-weight: bold;
  color: var(--accent-gold);
}

.player-marker.black {
  color: var(--text-light);
}

.move-count {
  color: var(--accent-gold);
}

/* 游戏控制面板 */
.game-control-section {
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.control-group {
  background: var(--secondary-dark);
  padding: 20px;
  border-radius: 8px;
  border: 1px solid var(--border-color);
}

.control-group h3 {
  color: var(--accent-gold);
  margin-bottom: 15px;
  font-size: 14px;
  text-transform: uppercase;
  letter-spacing: 1px;
}

.button-group {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.button-group .btn {
  width: 100%;
  padding: 10px;
  font-size: 14px;
}

.radio-label {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 10px;
  cursor: pointer;
  color: var(--text-light);
}

.radio-label input[type="radio"] {
  cursor: pointer;
  accent-color: var(--accent-gold);
}

.status-box {
  background: var(--primary-dark);
  padding: 15px;
  border-left: 3px solid var(--accent-gold);
  border-radius: 4px;
  color: var(--text-light);
  min-height: 50px;
  display: flex;
  align-items: center;
  font-size: 14px;
}

.move-history {
  background: var(--primary-dark);
  padding: 15px;
  border-radius: 4px;
  max-height: 150px;
  overflow-y: auto;
  font-size: 13px;
  color: var(--text-muted);
}

.move-history .empty-text {
  color: var(--text-muted);
  font-style: italic;
}

.move-history .move-item {
  padding: 5px 0;
  border-bottom: 1px solid var(--border-color);
}

.move-history .move-item:last-child {
  border-bottom: none;
}

/* 规则页面 */
.rules-container {
  padding: 60px 0;
  min-height: calc(100vh - 80px);
}

.rules-container h1 {
  font-size: 36px;
  margin-bottom: 40px;
  color: var(--accent-gold);
}

.rule-section {
  margin-bottom: 50px;
  background: var(--secondary-dark);
  padding: 30px;
  border-radius: 8px;
  border-left: 4px solid var(--accent-gold);
}

.rule-section h2 {
  color: var(--accent-gold);
  margin-bottom: 20px;
  font-size: 24px;
}

.rule-content h3 {
  color: var(--text-light);
  margin-top: 20px;
  margin-bottom: 10px;
}

.rule-content ul,
.rule-content ol {
  margin-left: 20px;
  margin-bottom: 15px;
  color: var(--text-light);
  line-height: 1.8;
}

.rule-content li {
  margin-bottom: 8px;
}

.rule-content p {
  color: var(--text-light);
  line-height: 1.8;
  margin-bottom: 15px;
}

.rules-footer {
  text-align: center;
  margin-top: 50px;
}

/* 排行榜页面 */
.leaderboard-container {
  padding: 60px 0;
  min-height: calc(100vh - 80px);
}

.leaderboard-container h1 {
  font-size: 36px;
  margin-bottom: 40px;
  color: var(--accent-gold);
}

.leaderboard-tabs {
  display: flex;
  gap: 10px;
  margin-bottom: 30px;
  border-bottom: 2px solid var(--border-color);
}

.tab-btn {
  background: none;
  border: none;
  color: var(--text-muted);
  padding: 12px 20px;
  font-size: 16px;
  cursor: pointer;
  border-bottom: 3px solid transparent;
  transition: all 0.3s;
}

.tab-btn.active {
  color: var(--accent-gold);
  border-bottom-color: var(--accent-gold);
}

.tab-btn:hover {
  color: var(--accent-gold);
}

.leaderboard-table {
  background: var(--secondary-dark);
  border-radius: 8px;
  overflow: hidden;
  border: 1px solid var(--border-color);
  margin-bottom: 50px;
}

.leaderboard-table table {
  width: 100%;
  border-collapse: collapse;
}

.leaderboard-table thead {
  background: var(--primary-dark);
  border-bottom: 2px solid var(--accent-gold);
}

.leaderboard-table th {
  padding: 15px;
  text-align: left;
  color: var(--accent-gold);
  font-weight: 600;
  text-transform: uppercase;
  font-size: 13px;
}

.leaderboard-table th.rank {
  width: 60px;
  text-align: center;
}

.leaderboard-table th.player {
  width: 200px;
}

.leaderboard-table th.rating,
.leaderboard-table th.wins,
.leaderboard-table th.losses,
.leaderboard-table th.winrate {
  width: 100px;
  text-align: center;
}

.leaderboard-table td {
  padding: 15px;
  border-bottom: 1px solid var(--border-color);
  color: var(--text-light);
}

.leaderboard-table td.rank {
  text-align: center;
  font-weight: bold;
  color: var(--accent-gold);
}

.leaderboard-table td.player {
  font-weight: 500;
}

.leaderboard-table td.rating,
.leaderboard-table td.wins,
.leaderboard-table td.losses,
.leaderboard-table td.winrate {
  text-align: center;
}

.leaderboard-table tbody tr:hover {
  background: var(--primary-dark);
}

.stats-section h2 {
  font-size: 28px;
  margin-bottom: 30px;
  color: var(--accent-gold);
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 20px;
}

.stat-card {
  background: var(--secondary-dark);
  padding: 30px;
  border-radius: 8px;
  border: 1px solid var(--border-color);
  text-align: center;
  transition: all 0.3s;
}

.stat-card:hover {
  border-color: var(--accent-gold);
  transform: translateY(-5px);
}

.stat-number {
  font-size: 36px;
  font-weight: bold;
  color: var(--accent-gold);
  margin-bottom: 10px;
}

.stat-label {
  color: var(--text-muted);
  font-size: 14px;
  text-transform: uppercase;
  letter-spacing: 1px;
}

/* 隐私政策页面 */
.policy-container {
  padding: 60px 0;
  min-height: calc(100vh - 80px);
}

.policy-header {
  margin-bottom: 50px;
  text-align: center;
  border-bottom: 2px solid var(--accent-gold);
  padding-bottom: 30px;
}

.policy-header h1 {
  font-size: 36px;
  color: var(--accent-gold);
  margin-bottom: 10px;
}

.last-updated {
  color: var(--text-muted);
  font-size: 14px;
}

.policy-content {
  max-width: 900px;
  margin: 0 auto;
}

.policy-section {
  margin-bottom: 40px;
  background: var(--secondary-dark);
  padding: 30px;
  border-radius: 8px;
  border-left: 4px solid var(--accent-gold);
}

.policy-section h2 {
  color: var(--accent-gold);
  margin-bottom: 20px;
  font-size: 22px;
}

.policy-section h3 {
  color: var(--text-light);
  margin-top: 20px;
  margin-bottom: 15px;
  font-size: 16px;
}

.policy-section p {
  color: var(--text-light);
  line-height: 1.8;
  margin-bottom: 15px;
}

.policy-section ul,
.policy-section ol {
  margin-left: 20px;
  margin-bottom: 15px;
  color: var(--text-light);
  line-height: 1.8;
}

.policy-section li {
  margin-bottom: 10px;
}

.contact-info {
  background: var(--primary-dark);
  padding: 20px;
  border-radius: 6px;
  border-left: 3px solid var(--accent-gold);
  margin-top: 20px;
}

.contact-info p {
  margin-bottom: 10px;
  color: var(--text-light);
}

.contact-info a {
  color: var(--accent-gold);
  text-decoration: none;
  transition: color 0.3s;
}

.contact-info a:hover {
  color: #e6c746;
}

/* 响应式设计 */
@media (max-width: 768px) {
  .nav-menu {
    gap: 15px;
    font-size: 14px;
  }

  .hero {
    flex-direction: column;
    padding: 50px 0;
    gap: 40px;
  }

  .hero h2 {
    font-size: 32px;
  }

  .hero-board canvas {
    width: 100%;
    max-width: 300px;
    height: auto;
  }

  .intro-content {
    flex-direction: column;
    gap: 40px;
  }

  .game-wrapper {
    grid-template-columns: 1fr;
  }

  .game-control-section {
    order: -1;
  }

  .features-grid {
    grid-template-columns: 1fr;
  }

  .leaderboard-table {
    font-size: 14px;
  }

  .leaderboard-table th,
  .leaderboard-table td {
    padding: 10px;
  }
}