/* roulang page: index */
:root {
      --primary: #1A5F7A;
      --secondary: #0EA5E9;
      --accent: #F59E0B;
      --bg: #F8FAFC;
      --card-bg: #FFFFFF;
      --text: #1E293B;
      --text-secondary: #64748B;
      --text-muted: #94A3B8;
      --border: #E2E8F0;
      --shadow-sm: 0 1px 3px rgba(0,0,0,0.06), 0 1px 2px rgba(0,0,0,0.04);
      --shadow-md: 0 4px 12px rgba(26,95,122,0.08), 0 2px 6px rgba(26,95,122,0.04);
      --shadow-hover: 0 10px 25px rgba(26,95,122,0.12), 0 4px 10px rgba(26,95,122,0.06);
      --radius-sm: 8px;
      --radius: 12px;
      --radius-xl: 16px;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", "Inter", sans-serif;
      --transition: 0.3s ease;
      --container: 1200px;
      --nav-height: 72px;
    }

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

    body {
      font-family: var(--font-sans);
      background-color: var(--bg);
      color: var(--text);
      line-height: 1.75;
      -webkit-font-smoothing: antialiased;
    }

    .container {
      max-width: var(--container);
      margin: 0 auto;
      padding: 0 24px;
    }

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

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

    button, .btn {
      cursor: pointer;
      font-family: inherit;
      border: none;
      background: none;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 6px;
      transition: all var(--transition);
    }

    h1, h2, h3, h4 {
      line-height: 1.3;
    }

    /* 导航 */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      background: rgba(255,255,255,0.92);
      backdrop-filter: blur(12px);
      box-shadow: 0 2px 8px rgba(0,0,0,0.04);
      z-index: 1000;
      height: var(--nav-height);
      display: flex;
      align-items: center;
    }

    .nav {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
    }

    .logo {
      font-size: 1.6rem;
      font-weight: 700;
      color: var(--primary);
      letter-spacing: -0.3px;
    }
    .logo i {
      color: var(--accent);
      margin-right: 6px;
    }

    .nav-links {
      display: flex;
      gap: 8px;
      background: #F1F5F9;
      padding: 6px;
      border-radius: 40px;
    }

    .nav-links a {
      padding: 8px 18px;
      border-radius: 30px;
      font-weight: 500;
      font-size: 0.95rem;
      color: var(--text-secondary);
      transition: all 0.2s;
    }

    .nav-links a:hover {
      background: #E2E8F0;
      color: var(--text);
    }

    .nav-cta {
      background: var(--secondary);
      color: white;
      padding: 10px 24px;
      border-radius: 30px;
      font-weight: 600;
      font-size: 0.95rem;
      box-shadow: 0 4px 10px rgba(14,165,233,0.25);
    }
    .nav-cta:hover {
      background: #0284C7;
      box-shadow: 0 6px 14px rgba(14,165,233,0.35);
    }

    .hamburger {
      display: none;
      font-size: 1.8rem;
      color: var(--text);
    }

    .mobile-menu {
      display: none;
      position: fixed;
      top: var(--nav-height);
      left: 0;
      width: 100%;
      background: white;
      flex-direction: column;
      padding: 24px;
      box-shadow: var(--shadow-md);
      z-index: 999;
      gap: 16px;
      transform: translateY(-10px);
      opacity: 0;
      pointer-events: none;
      transition: 0.25s ease;
    }
    .mobile-menu.active {
      transform: translateY(0);
      opacity: 1;
      pointer-events: auto;
    }
    .mobile-menu a {
      font-size: 1.2rem;
      font-weight: 500;
      padding: 12px 0;
      border-bottom: 1px solid var(--border);
      display: block;
    }

    /* Hero */
    .hero {
      padding: 120px 0 80px;
      background: linear-gradient(135deg, #F0F4F8 0%, #E6F0F5 100%);
      position: relative;
      overflow: hidden;
    }
    .hero .container {
      display: flex;
      align-items: center;
      gap: 48px;
    }
    .hero-content {
      flex: 1;
    }
    .hero-content h1 {
      font-size: 48px;
      font-weight: 700;
      letter-spacing: -0.5px;
      color: var(--text);
      margin-bottom: 16px;
    }
    .hero-content h1 span {
      color: var(--secondary);
    }
    .hero-sub {
      font-size: 1.2rem;
      color: var(--text-secondary);
      margin-bottom: 32px;
      max-width: 480px;
    }
    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }
    .btn-primary {
      background: var(--secondary);
      color: white;
      padding: 14px 32px;
      border-radius: 30px;
      font-weight: 600;
      box-shadow: 0 4px 12px rgba(14,165,233,0.3);
    }
    .btn-primary:hover {
      background: #0284C7;
      transform: translateY(-1px);
    }
    .btn-outline {
      border: 2px solid var(--secondary);
      color: var(--secondary);
      padding: 12px 30px;
      border-radius: 30px;
      font-weight: 600;
    }
    .btn-outline:hover {
      background: var(--secondary);
      color: white;
    }
    .hero-mockup {
      flex: 1;
      animation: float 4s ease-in-out infinite;
      max-width: 420px;
    }
    @keyframes float {
      0%, 100% { transform: translateY(0); }
      50% { transform: translateY(-10px); }
    }

    /* 板块通用 */
    section {
      padding: 80px 0;
    }
    .section-title {
      font-size: 36px;
      font-weight: 600;
      margin-bottom: 16px;
      text-align: center;
      color: var(--text);
    }
    .section-sub {
      color: var(--text-secondary);
      text-align: center;
      max-width: 600px;
      margin: 0 auto 48px;
    }

    /* 特色卡片 */
    .features-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
    }
    .feature-card {
      background: var(--card-bg);
      padding: 32px 24px;
      border-radius: var(--radius);
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
      text-align: center;
    }
    .feature-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
    }
    .feature-icon {
      font-size: 2.4rem;
      color: var(--secondary);
      margin-bottom: 16px;
    }

    /* 场景交替 */
    .scenario-row {
      display: flex;
      align-items: center;
      gap: 48px;
      margin-bottom: 64px;
    }
    .scenario-row.reverse {
      flex-direction: row-reverse;
    }
    .scenario-text {
      flex: 1;
    }
    .scenario-img {
      flex: 1;
      border-radius: var(--radius-xl);
      overflow: hidden;
      box-shadow: var(--shadow-md);
    }

    /* 案例 */
    .stats {
      display: flex;
      justify-content: center;
      gap: 48px;
      margin-bottom: 48px;
    }
    .stat-item {
      text-align: center;
    }
    .stat-number {
      font-size: 2.8rem;
      font-weight: 700;
      color: var(--primary);
    }
    .cases-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .case-card {
      background: var(--card-bg);
      padding: 28px;
      border-radius: var(--radius);
      box-shadow: var(--shadow-sm);
    }
    .case-avatar {
      width: 48px;
      height: 48px;
      border-radius: 50%;
      background: #CBD5E1;
      margin-bottom: 12px;
    }

    /* 价格 */
    .pricing-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .pricing-card {
      background: white;
      padding: 32px;
      border-radius: var(--radius);
      box-shadow: var(--shadow-sm);
      text-align: center;
    }
    .pricing-card.featured {
      border: 2px solid var(--secondary);
      background: #F0F9FF;
      transform: scale(1.02);
    }
    .badge {
      background: var(--accent);
      color: white;
      padding: 4px 14px;
      border-radius: 20px;
      font-size: 0.8rem;
      font-weight: 600;
    }

    /* FAQ */
    .faq-item {
      border-bottom: 1px solid var(--border);
      padding: 20px 0;
      cursor: pointer;
    }
    .faq-question {
      font-weight: 600;
      display: flex;
      justify-content: space-between;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      color: var(--text-secondary);
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      margin-top: 12px;
    }

    /* CTA */
    .cta-section {
      background: linear-gradient(135deg, #1A5F7A 0%, #0E7490 100%);
      color: white;
      text-align: center;
      border-radius: 32px;
      margin: 0 24px 80px;
      padding: 64px 24px;
    }

    /* 页脚 */
    .footer {
      background: #1E293B;
      color: #CBD5E1;
      padding: 60px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr;
      gap: 40px;
    }
    .copyright {
      border-top: 1px solid #334155;
      margin-top: 40px;
      padding-top: 24px;
      text-align: center;
    }

    @media (max-width: 1024px) {
      .features-grid { grid-template-columns: repeat(2, 1fr); }
      .cases-grid { grid-template-columns: 1fr 1fr; }
      .pricing-grid { grid-template-columns: 1fr; max-width: 400px; margin: 0 auto; }
      .hero .container { flex-direction: column; text-align: center; }
      .hero-content h1 { font-size: 40px; }
    }
    @media (max-width: 768px) {
      .nav-links, .nav-cta { display: none; }
      .hamburger { display: block; }
      .features-grid, .cases-grid { grid-template-columns: 1fr; }
      .scenario-row { flex-direction: column; }
      .stats { flex-direction: column; gap: 24px; }
      .footer-grid { grid-template-columns: 1fr; }
      .hero-content h1 { font-size: 32px; }
      .section-title { font-size: 28px; }
    }