/* roulang page: index */
:root {
      --primary-deep: #0B1A2F;
      --accent-gold: #C9A96E;
      --accent-gold-hover: #D4B87A;
      --emphasis-purple: #6B5B95;
      --bg-light: #F7F8FA;
      --white: #FFFFFF;
      --text-primary: #1A202C;
      --text-secondary: #5A6B7F;
      --text-muted: #A0AEC0;
      --border-light: #E2E8F0;
      --shadow-card: 0 2px 12px rgba(11,26,47,0.06);
      --shadow-card-hover: 0 8px 24px rgba(11,26,47,0.12);
      --radius-card: 12px;
      --radius-button: 8px;
      --font-sans: -apple-system, "PingFang SC", "Microsoft YaHei", "Inter", system-ui, sans-serif;
      --transition-base: all 0.25s ease;
      --container-max: 1200px;
      --nav-height: 64px;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    body {
      font-family: var(--font-sans);
      background-color: var(--bg-light);
      color: var(--text-primary);
      line-height: 1.7;
      -webkit-font-smoothing: antialiased;
      overflow-x: hidden;
    }
    img {
      max-width: 100%;
      height: auto;
      display: block;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: var(--transition-base);
    }
    .container {
      width: 100%;
      max-width: var(--container-max);
      margin: 0 auto;
      padding: 0 20px;
    }
    /* 导航 */
    .site-header {
      position: sticky;
      top: 0;
      z-index: 50;
      background: var(--white);
      box-shadow: 0 1px 0 rgba(0,0,0,0.05);
      height: var(--nav-height);
    }
    .nav-bar {
      display: flex;
      align-items: center;
      justify-content: space-between;
      height: 100%;
    }
    .logo {
      font-size: 20px;
      font-weight: 700;
      color: var(--primary-deep);
      letter-spacing: 0.5px;
      display: flex;
      align-items: center;
      gap: 6px;
    }
    .logo i {
      color: var(--accent-gold);
      font-size: 22px;
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 28px;
    }
    .nav-links a {
      font-size: 15px;
      color: var(--text-secondary);
      font-weight: 500;
      padding: 8px 0;
      border-bottom: 2px solid transparent;
    }
    .nav-links a:hover {
      color: var(--primary-deep);
      border-bottom-color: var(--accent-gold);
    }
    .nav-cta {
      background: transparent;
      border: 1.5px solid var(--primary-deep);
      color: var(--primary-deep);
      padding: 8px 18px;
      border-radius: var(--radius-button);
      font-weight: 600;
      font-size: 14px;
      transition: var(--transition-base);
      white-space: nowrap;
    }
    .nav-cta:hover {
      background: rgba(11,26,47,0.04);
      border-color: var(--accent-gold);
      color: var(--accent-gold);
    }
    .hamburger {
      display: none;
      flex-direction: column;
      gap: 5px;
      cursor: pointer;
      background: none;
      border: none;
      padding: 8px;
    }
    .hamburger span {
      width: 24px;
      height: 2px;
      background: var(--primary-deep);
      border-radius: 2px;
      transition: var(--transition-base);
    }
    .mobile-menu {
      position: fixed;
      top: 0;
      right: 0;
      width: 80%;
      max-width: 320px;
      height: 100vh;
      background: var(--primary-deep);
      z-index: 100;
      transform: translateX(100%);
      transition: transform 0.3s ease;
      display: flex;
      flex-direction: column;
      padding: 30px 24px;
      box-shadow: -8px 0 24px rgba(0,0,0,0.2);
    }
    .mobile-menu.active {
      transform: translateX(0);
    }
    .mobile-close {
      align-self: flex-end;
      background: none;
      border: none;
      color: var(--white);
      font-size: 28px;
      cursor: pointer;
      margin-bottom: 30px;
    }
    .mobile-menu a {
      color: rgba(255,255,255,0.85);
      font-size: 18px;
      padding: 14px 0;
      border-bottom: 1px solid rgba(255,255,255,0.15);
      display: block;
    }
    .mobile-menu a:hover {
      color: var(--accent-gold);
    }
    /* Hero */
    .hero {
      background: linear-gradient(135deg, #F7F8FA 0%, #FFFFFF 100%);
      padding: 80px 0;
      position: relative;
      overflow: hidden;
    }
    .hero::before {
      content: "";
      position: absolute;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      background-image: radial-gradient(circle at 30% 70%, rgba(201,169,110,0.08) 0%, transparent 40%);
      pointer-events: none;
    }
    .hero-grid {
      display: flex;
      align-items: center;
      gap: 40px;
      position: relative;
      z-index: 2;
    }
    .hero-content {
      flex: 1 1 55%;
    }
    .hero h1 {
      font-size: clamp(32px, 5vw, 44px);
      font-weight: 700;
      color: var(--primary-deep);
      line-height: 1.25;
      margin-bottom: 20px;
    }
    .hero-sub {
      font-size: 18px;
      color: var(--text-secondary);
      max-width: 480px;
      margin-bottom: 32px;
      line-height: 1.7;
    }
    .btn-primary {
      background: var(--primary-deep);
      color: white;
      padding: 12px 28px;
      border-radius: var(--radius-button);
      font-weight: 600;
      font-size: 16px;
      display: inline-block;
      border: none;
      cursor: pointer;
      transition: var(--transition-base);
      text-align: center;
    }
    .btn-primary:hover {
      background: #132B45;
      transform: translateY(-1px);
    }
    .hero-image {
      flex: 1 1 45%;
      position: relative;
    }
    .hero-image img {
      border-radius: 20px;
      box-shadow: 0 20px 35px rgba(11,26,47,0.12);
      width: 100%;
      object-fit: cover;
    }
    /* 通用区块 */
    .section {
      padding: 80px 0;
    }
    .section-title {
      font-size: 30px;
      font-weight: 700;
      color: var(--primary-deep);
      margin-bottom: 16px;
      text-align: center;
    }
    .section-lead {
      text-align: center;
      color: var(--text-secondary);
      max-width: 680px;
      margin: 0 auto 48px;
      font-size: 17px;
    }
    /* 优势区 - 非标准卡片流 */
    .advantage-row {
      display: flex;
      flex-wrap: wrap;
      gap: 32px;
      justify-content: center;
    }
    .adv-item {
      flex: 1 1 220px;
      display: flex;
      align-items: flex-start;
      gap: 16px;
      background: transparent;
      padding: 12px 8px;
    }
    .adv-icon {
      color: var(--accent-gold);
      font-size: 28px;
      margin-top: 4px;
      flex-shrink: 0;
    }
    .adv-text h3 {
      font-size: 20px;
      font-weight: 700;
      color: var(--primary-deep);
      margin-bottom: 6px;
    }
    .adv-text p {
      color: var(--text-secondary);
      font-size: 15px;
      line-height: 1.6;
    }
    /* 功能卡片 */
    .cards-grid {
      display: grid;
      grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
      gap: 28px;
    }
    .feature-card {
      background: var(--white);
      border-radius: var(--radius-card);
      padding: 28px 24px;
      box-shadow: var(--shadow-card);
      transition: var(--transition-base);
      display: flex;
      flex-direction: column;
    }
    .feature-card:hover {
      box-shadow: var(--shadow-card-hover);
      transform: translateY(-3px);
    }
    .feature-img {
      width: 100%;
      height: 140px;
      object-fit: cover;
      border-radius: 8px;
      margin-bottom: 18px;
    }
    .feature-card h3 {
      font-size: 22px;
      font-weight: 700;
      margin-bottom: 10px;
    }
    .feature-card p {
      color: var(--text-secondary);
      font-size: 15px;
      flex: 1;
    }
    /* 场景卡片 */
    .scene-card {
      background: var(--white);
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--shadow-card);
      display: flex;
      flex-direction: column;
    }
    .scene-img {
      width: 100%;
      height: 180px;
      object-fit: cover;
    }
    .scene-body {
      padding: 20px 24px;
    }
    .scene-body h3 {
      font-size: 20px;
      font-weight: 700;
      margin-bottom: 8px;
    }
    .tag {
      background: #F0F2F5;
      color: var(--primary-deep);
      padding: 4px 12px;
      border-radius: 20px;
      font-size: 13px;
      display: inline-block;
      margin-top: 10px;
    }
    /* 数据卡片 */
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4,1fr);
      gap: 24px;
      text-align: center;
    }
    .stat-item {
      background: var(--white);
      padding: 28px 16px;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-card);
    }
    .stat-number {
      font-size: 34px;
      font-weight: 700;
      color: var(--emphasis-purple);
    }
    .stat-label {
      color: var(--text-secondary);
      margin-top: 6px;
    }
    /* 价格卡片 */
    .pricing-grid {
      display: flex;
      flex-wrap: wrap;
      gap: 24px;
      justify-content: center;
    }
    .pricing-card {
      background: var(--white);
      border-radius: var(--radius-card);
      padding: 32px 24px;
      box-shadow: var(--shadow-card);
      flex: 1 1 240px;
      max-width: 280px;
      text-align: center;
      border: 2px solid transparent;
      position: relative;
    }
    .pricing-card.recommended {
      border-color: var(--accent-gold);
      box-shadow: 0 6px 20px rgba(201,169,110,0.2);
    }
    .badge {
      background: var(--accent-gold);
      color: var(--primary-deep);
      font-weight: 700;
      font-size: 12px;
      padding: 4px 14px;
      border-radius: 20px;
      position: absolute;
      top: -12px;
      left: 50%;
      transform: translateX(-50%);
    }
    .price {
      font-size: 38px;
      font-weight: 700;
      color: var(--primary-deep);
      margin: 16px 0 8px;
    }
    .btn-outline {
      border: 1.5px solid var(--primary-deep);
      background: transparent;
      color: var(--primary-deep);
      padding: 10px 22px;
      border-radius: var(--radius-button);
      font-weight: 600;
      display: inline-block;
    }
    .btn-gold {
      background: var(--accent-gold);
      color: var(--primary-deep);
      font-weight: 700;
      padding: 12px 26px;
      border-radius: var(--radius-button);
    }
    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }
    details {
      background: var(--white);
      border-radius: 10px;
      margin-bottom: 12px;
      padding: 16px 20px;
      box-shadow: 0 1px 6px rgba(0,0,0,0.03);
    }
    summary {
      font-weight: 700;
      color: var(--primary-deep);
      cursor: pointer;
      list-style: none;
      display: flex;
      justify-content: space-between;
    }
    summary::-webkit-details-marker {
      display: none;
    }
    .faq-answer {
      margin-top: 12px;
      color: var(--text-secondary);
      font-size: 15px;
    }
    /* CTA 横幅 */
    .cta-banner {
      background: var(--primary-deep);
      color: white;
      text-align: center;
      padding: 80px 20px;
    }
    .cta-banner h2 {
      font-size: 32px;
      margin-bottom: 16px;
    }
    /* 页脚 */
    .footer {
      background: var(--primary-deep);
      color: var(--text-muted);
      padding: 48px 0 24px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: repeat(4,1fr);
      gap: 30px;
    }
    .footer a {
      color: #CBD5E0;
      font-size: 14px;
    }
    .footer a:hover {
      color: var(--accent-gold);
    }
    .copyright {
      border-top: 1px solid rgba(255,255,255,0.1);
      margin-top: 32px;
      padding-top: 20px;
      text-align: center;
      font-size: 14px;
    }
    @media (max-width: 992px) {
      .hero-grid {
        flex-direction: column;
      }
      .stats-grid {
        grid-template-columns: repeat(2,1fr);
      }
      .footer-grid {
        grid-template-columns: repeat(2,1fr);
      }
    }
    @media (max-width: 768px) {
      .nav-links {
        display: none;
      }
      .hamburger {
        display: flex;
      }
      .section {
        padding: 60px 0;
      }
      .cards-grid, .pricing-grid {
        grid-template-columns: 1fr;
      }
    }
    @media (max-width: 520px) {
      .advantage-row {
        flex-direction: column;
      }
    }