/* roulang page: index */
:root {
      --primary: #0A84FF;
      --primary-dark: #0066CC;
      --accent: #FF6B35;
      --accent-hover: #E55A2B;
      --bg-light: #F8FAFC;
      --bg-white: #FFFFFF;
      --bg-dark: #0F172A;
      --bg-soft: #EEF2FF;
      --text-main: #1E293B;
      --text-secondary: #475569;
      --text-muted: #64748B;
      --text-light: #CBD5E1;
      --border-light: #E2E8F0;
      --radius-lg: 16px;
      --radius-md: 12px;
      --radius-sm: 8px;
      --shadow-card: 0 1px 3px rgba(0,0,0,0.04), 0 4px 12px rgba(0,0,0,0.06);
      --shadow-hover: 0 4px 16px rgba(10,132,255,0.12), 0 8px 24px rgba(0,0,0,0.08);
      --font-sans: "PingFang SC", "Microsoft YaHei", "Noto Sans SC", "Inter", "SF Pro Display", sans-serif;
    }

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

    body {
      font-family: var(--font-sans);
      background-color: var(--bg-light);
      color: var(--text-main);
      line-height: 1.6;
      -webkit-font-smoothing: antialiased;
      scroll-behavior: smooth;
    }

    a {
      text-decoration: none;
      color: inherit;
      transition: color 0.2s;
    }

    img {
      max-width: 100%;
      height: auto;
      display: block;
    }

    button, .btn {
      cursor: pointer;
      font-family: inherit;
      transition: all 0.25s ease;
      border: none;
      outline: none;
    }

    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 24px;
    }

    /* 导航 */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 72px;
      background: rgba(255,255,255,0.85);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      z-index: 1000;
      transition: box-shadow 0.3s;
      border-bottom: 1px solid rgba(226,232,240,0.4);
    }
    .header-scrolled {
      box-shadow: 0 4px 20px rgba(0,0,0,0.04);
    }
    .header-inner {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 72px;
    }
    .logo {
      font-size: 22px;
      font-weight: 700;
      color: var(--primary);
      display: flex;
      align-items: center;
      gap: 8px;
      letter-spacing: -0.3px;
    }
    .logo i {
      font-size: 24px;
      color: var(--accent);
    }
    .nav-menu {
      display: flex;
      align-items: center;
      gap: 32px;
    }
    .nav-link {
      font-size: 15px;
      font-weight: 500;
      color: var(--text-secondary);
      position: relative;
      padding: 4px 0;
    }
    .nav-link:hover,
    .nav-link.active {
      color: var(--primary);
    }
    .nav-link.active::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 100%;
      height: 2px;
      background: var(--primary);
      border-radius: 1px;
    }
    .btn-primary {
      background: var(--accent);
      color: white;
      padding: 12px 28px;
      border-radius: var(--radius-md);
      font-weight: 600;
      font-size: 16px;
      letter-spacing: 0.5px;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      box-shadow: 0 2px 8px rgba(255,107,53,0.2);
    }
    .btn-primary:hover {
      background: var(--accent-hover);
      transform: scale(1.02);
    }
    .btn-outline {
      background: transparent;
      border: 1.5px solid var(--primary);
      color: var(--primary);
      padding: 12px 28px;
      border-radius: var(--radius-md);
      font-weight: 600;
      font-size: 16px;
      letter-spacing: 0.5px;
    }
    .btn-outline:hover {
      background: rgba(10,132,255,0.08);
    }
    .hamburger {
      display: none;
      font-size: 24px;
      background: none;
      border: none;
      color: var(--text-main);
    }
    .mobile-menu {
      display: none;
      position: fixed;
      top: 72px;
      left: 0;
      width: 100%;
      background: rgba(255,255,255,0.98);
      backdrop-filter: blur(16px);
      flex-direction: column;
      padding: 24px;
      gap: 20px;
      box-shadow: 0 10px 25px rgba(0,0,0,0.1);
      z-index: 999;
    }
    .mobile-menu a {
      font-size: 18px;
      font-weight: 500;
    }

    /* Hero */
    .hero {
      padding: 120px 0 100px;
      background: radial-gradient(circle at 20% 30%, rgba(10,132,255,0.12) 0%, transparent 60%);
      min-height: 85vh;
      display: flex;
      align-items: center;
    }
    .hero-grid {
      display: flex;
      align-items: center;
      gap: 60px;
    }
    .hero-text {
      flex: 1 1 55%;
    }
    .hero h1 {
      font-size: 48px;
      font-weight: 700;
      line-height: 1.2;
      letter-spacing: -0.5px;
      color: var(--text-main);
    }
    .hero-sub {
      font-size: 20px;
      color: var(--text-secondary);
      margin: 20px 0 16px;
      font-weight: 500;
    }
    .hero-desc {
      font-size: 16px;
      color: var(--text-muted);
      max-width: 480px;
      margin-bottom: 32px;
    }
    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .hero-image {
      flex: 1 1 45%;
      animation: float 4s ease-in-out infinite;
    }
    @keyframes float {
      0% { transform: translateY(0); }
      50% { transform: translateY(-12px); }
      100% { transform: translateY(0); }
    }

    /* 通用标题 */
    .section-title {
      font-size: 36px;
      font-weight: 600;
      margin-bottom: 16px;
      letter-spacing: -0.3px;
    }
    .section-desc {
      color: var(--text-muted);
      max-width: 700px;
      margin-bottom: 48px;
      font-size: 16px;
    }

    /* 优势非对称 */
    .advantage-grid {
      display: grid;
      grid-template-columns: 1.2fr 0.8fr;
      gap: 24px;
    }
    .big-card {
      background: var(--bg-white);
      border-radius: var(--radius-lg);
      padding: 36px;
      box-shadow: var(--shadow-card);
      transition: all 0.3s;
      background-image: radial-gradient(circle at top right, rgba(10,132,255,0.05), transparent 50%);
    }
    .small-cards {
      display: flex;
      flex-direction: column;
      gap: 24px;
    }
    .small-card {
      background: var(--bg-white);
      border-radius: var(--radius-md);
      padding: 28px;
      box-shadow: var(--shadow-card);
      transition: all 0.3s;
    }
    .big-card:hover, .small-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }
    .icon-circle {
      width: 48px;
      height: 48px;
      background: rgba(10,132,255,0.1);
      border-radius: 12px;
      display: flex;
      align-items: center;
      justify-content: center;
      color: var(--primary);
      font-size: 24px;
      margin-bottom: 20px;
    }

    /* 游戏卡片 */
    .games-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .game-card {
      background: var(--bg-white);
      border-radius: var(--radius-lg);
      overflow: hidden;
      box-shadow: var(--shadow-card);
      transition: all 0.3s;
      position: relative;
    }
    .game-card:hover {
      transform: translateY(-8px);
      box-shadow: var(--shadow-hover);
    }
    .game-img {
      position: relative;
      aspect-ratio: 16/9;
      overflow: hidden;
      background: #f1f5f9;
    }
    .game-img img {
      width: 100%;
      height: 100%;
      object-fit: cover;
    }
    .game-overlay {
      position: absolute;
      inset: 0;
      background: rgba(10,132,255,0.7);
      display: flex;
      align-items: center;
      justify-content: center;
      opacity: 0;
      transition: 0.3s;
      color: white;
      font-weight: 600;
      font-size: 16px;
    }
    .game-card:hover .game-overlay {
      opacity: 1;
    }
    .game-info {
      padding: 20px;
    }
    .game-info h3 {
      font-size: 20px;
      font-weight: 600;
      margin-bottom: 6px;
    }
    .game-info p {
      font-size: 14px;
      color: var(--text-muted);
    }

    /* 步骤 */
    .steps-container {
      display: flex;
      justify-content: space-between;
      align-items: flex-start;
      position: relative;
      gap: 20px;
    }
    .step-item {
      flex: 1;
      text-align: center;
      position: relative;
      z-index: 2;
    }
    .step-num {
      width: 48px;
      height: 48px;
      background: var(--primary);
      color: white;
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      font-weight: 700;
      font-size: 20px;
      margin: 0 auto 16px;
      box-shadow: 0 0 0 8px rgba(10,132,255,0.15);
      animation: pulse 2s infinite;
    }
    @keyframes pulse {
      0% { box-shadow: 0 0 0 8px rgba(10,132,255,0.15); }
      50% { box-shadow: 0 0 0 16px rgba(10,132,255,0.05); }
      100% { box-shadow: 0 0 0 8px rgba(10,132,255,0.15); }
    }
    .step-line {
      position: absolute;
      top: 24px;
      left: 0;
      width: 100%;
      height: 2px;
      background: repeating-linear-gradient(90deg, var(--primary) 0px, var(--primary) 8px, transparent 8px, transparent 16px);
      z-index: 1;
    }
    .step-title {
      font-weight: 600;
      font-size: 18px;
    }
    .step-desc {
      color: var(--text-muted);
      font-size: 14px;
    }

    /* 数据 */
    .stats-bg {
      background: var(--bg-dark);
      border-radius: var(--radius-lg);
      padding: 60px 40px;
    }
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 30px;
      text-align: center;
    }
    .stat-number {
      font-size: 40px;
      font-weight: 700;
      color: var(--primary);
    }
    .stat-label {
      color: var(--text-light);
      font-size: 14px;
      margin-top: 8px;
    }

    /* FAQ */
    .faq-grid {
      display: grid;
      grid-template-columns: 1fr 300px;
      gap: 40px;
      align-items: start;
    }
    .accordion-item {
      border-bottom: 1px solid var(--border-light);
      padding: 18px 0;
    }
    .accordion-header {
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-weight: 600;
      font-size: 16px;
      cursor: pointer;
    }
    .accordion-content {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      color: var(--text-secondary);
      font-size: 15px;
      margin-top: 8px;
    }
    .faq-sidecard {
      background: var(--bg-soft);
      border-radius: var(--radius-lg);
      padding: 32px;
    }

    /* CTA 横幅 */
    .cta-band {
      background: linear-gradient(135deg, #0A84FF 0%, #0066CC 100%);
      padding: 80px 0;
      text-align: center;
      color: white;
      border-radius: 0;
    }
    .cta-band h2 {
      font-size: 36px;
    }
    .btn-white {
      background: white;
      color: var(--primary);
      padding: 14px 36px;
      border-radius: var(--radius-md);
      font-weight: 700;
    }

    /* 页脚 */
    .footer {
      background: #1E293B;
      color: var(--text-light);
      padding: 60px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
    }
    .footer a:hover {
      color: var(--primary);
    }
    .copyright {
      border-top: 1px solid #334155;
      margin-top: 40px;
      padding-top: 20px;
      text-align: center;
      font-size: 14px;
    }

    @media (max-width: 1024px) {
      .hero-grid {
        flex-direction: column;
      }
      .steps-container {
        flex-wrap: wrap;
      }
      .step-line {
        display: none;
      }
      .faq-grid {
        grid-template-columns: 1fr;
      }
    }
    @media (max-width: 768px) {
      .nav-menu { display: none; }
      .hamburger { display: block; }
      .games-grid { grid-template-columns: 1fr 1fr; }
      .advantage-grid { grid-template-columns: 1fr; }
      .stats-grid { grid-template-columns: 1fr 1fr; }
      .footer-grid { grid-template-columns: 1fr; }
    }
    @media (max-width: 520px) {
      .games-grid { grid-template-columns: 1fr; }
    }