/* roulang page: index */
:root {
      --primary: #0A2E4D;
      --secondary: #F15A24;
      --accent: #00B4A6;
      --bg-light: #F7F9FC;
      --dark-bg: #0A1C2E;
      --card-bg: #FFFFFF;
      --text-main: #1E2B3C;
      --text-muted: #5A6B7F;
      --border-light: rgba(10, 46, 77, 0.08);
      --shadow-sm: 0 2px 8px rgba(10, 46, 77, 0.06);
      --shadow-hover: 0 12px 28px rgba(10, 46, 77, 0.12);
      --radius-card: 16px;
      --radius-btn: 12px;
      --radius-input: 8px;
      --transition: all 0.25s ease;
      --font-h1: 800 3rem/1.2 -apple-system, "PingFang SC", "Microsoft YaHei", "Noto Sans SC", sans-serif;
      --font-h2: 700 2rem/1.3 -apple-system, "PingFang SC", "Microsoft YaHei", sans-serif;
      --font-h3: 600 1.25rem/1.4 -apple-system, "PingFang SC", "Microsoft YaHei", sans-serif;
      --font-body: 400 1rem/1.7 -apple-system, "PingFang SC", "Microsoft YaHei", "Noto Sans SC", sans-serif;
      --font-small: 400 0.875rem/1.5 -apple-system, "PingFang SC", "Microsoft YaHei", sans-serif;
    }

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

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

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

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

    button, input {
      font-family: inherit;
    }

    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
    }

    /* 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 1px 0 var(--border-light);
      z-index: 100;
      height: 72px;
      display: flex;
      align-items: center;
    }

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

    .logo {
      display: flex;
      align-items: center;
      gap: 10px;
      font-weight: 700;
      font-size: 1.5rem;
      color: var(--primary);
    }

    .logo-icon {
      font-size: 2rem;
      color: var(--primary);
    }

    .nav-links {
      display: flex;
      gap: 2.5rem;
      align-items: center;
    }

    .nav-links a {
      font-weight: 500;
      color: var(--text-main);
      position: relative;
      padding: 8px 0;
    }

    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 3px;
      background: var(--secondary);
      transition: width 0.2s;
    }

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

    .menu-toggle {
      display: none;
      background: none;
      border: none;
      font-size: 1.8rem;
      color: var(--primary);
      cursor: pointer;
    }

    /* 移动端抽屉 */
    .mobile-menu {
      position: fixed;
      top: 0;
      left: -100%;
      width: 100%;
      height: 100vh;
      background: var(--primary);
      display: flex;
      flex-direction: column;
      justify-content: center;
      align-items: center;
      gap: 2.5rem;
      transition: left 0.35s ease;
      z-index: 200;
    }

    .mobile-menu.open {
      left: 0;
    }

    .mobile-menu a {
      color: white;
      font-size: 1.8rem;
      font-weight: 600;
    }

    .mobile-close {
      position: absolute;
      top: 24px;
      right: 24px;
      background: none;
      border: none;
      color: white;
      font-size: 2rem;
      cursor: pointer;
    }

    /* Hero */
    .hero {
      padding: 140px 0 80px;
      background: linear-gradient(135deg, #F7F9FC 0%, #E9EFF5 100%);
      position: relative;
      overflow: hidden;
    }

    .hero::before {
      content: '';
      position: absolute;
      right: -5%;
      top: 10%;
      width: 500px;
      height: 500px;
      background: radial-gradient(circle at 30% 30%, rgba(0,180,166,0.08) 0%, transparent 70%);
      border-radius: 50%;
    }

    .hero-grid {
      display: flex;
      align-items: center;
      gap: 3rem;
      position: relative;
      z-index: 2;
    }

    .hero-text {
      flex: 1 1 50%;
    }

    .hero-text h1 {
      font: var(--font-h1);
      color: var(--primary);
      margin-bottom: 1.5rem;
      letter-spacing: -0.02em;
    }

    .hero-sub {
      font-size: 1.25rem;
      color: var(--text-muted);
      margin-bottom: 2rem;
      max-width: 90%;
    }

    .btn-group {
      display: flex;
      gap: 1rem;
      flex-wrap: wrap;
    }

    .btn-primary {
      background: var(--primary);
      color: white;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      border: none;
      cursor: pointer;
      transition: var(--transition);
    }

    .btn-primary:hover {
      background: #07223A;
    }

    .btn-outline {
      background: transparent;
      border: 2px solid var(--primary);
      color: var(--primary);
      padding: 12px 30px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      transition: var(--transition);
    }

    .btn-outline:hover {
      background: rgba(10,46,77,0.06);
    }

    .hero-stats {
      flex: 1 1 45%;
      display: grid;
      grid-template-columns: repeat(2,1fr);
      gap: 1.5rem;
    }

    .stat-card {
      background: rgba(255,255,255,0.75);
      backdrop-filter: blur(10px);
      border-radius: var(--radius-card);
      padding: 1.8rem;
      box-shadow: var(--shadow-sm);
      border: 1px solid rgba(255,255,255,0.7);
    }

    .stat-number {
      font-size: 2.5rem;
      font-weight: 800;
      color: var(--secondary);
      line-height: 1.2;
    }

    .stat-label {
      color: var(--text-muted);
      font-size: 0.95rem;
      margin-top: 0.4rem;
    }

    /* 通用板块 */
    .section {
      padding: 80px 0;
    }

    .section-title {
      font: var(--font-h2);
      color: var(--primary);
      text-align: center;
      margin-bottom: 1rem;
    }

    .section-sub {
      color: var(--text-muted);
      text-align: center;
      max-width: 650px;
      margin: 0 auto 3rem;
    }

    /* 服务卡片 */
    .cards-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 1.8rem;
    }

    .feature-card {
      background: var(--card-bg);
      border-radius: var(--radius-card);
      padding: 2rem 1.8rem;
      box-shadow: var(--shadow-sm);
      transition: var(--transition);
      border: 1px solid transparent;
      position: relative;
      overflow: hidden;
    }

    .feature-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
      border-color: rgba(10,46,77,0.2);
    }

    .feature-icon {
      font-size: 2.5rem;
      color: var(--accent);
      margin-bottom: 1.5rem;
    }

    .feature-card h3 {
      font: var(--font-h3);
      margin-bottom: 0.8rem;
    }

    .feature-card p {
      color: var(--text-muted);
      margin-bottom: 1.5rem;
    }

    .text-link {
      color: var(--secondary);
      font-weight: 600;
      display: inline-flex;
      align-items: center;
      gap: 6px;
    }

    .text-link i {
      transition: transform 0.2s;
    }

    .text-link:hover i {
      transform: translateX(4px);
    }

    /* 数据看板 */
    .data-board {
      background: #F0F4FA;
      border-radius: 32px;
      padding: 2.5rem;
    }

    .data-grid {
      display: grid;
      grid-template-columns: repeat(4,1fr);
      gap: 1.5rem;
    }

    .data-item {
      background: white;
      border-radius: var(--radius-card);
      padding: 1.8rem;
      border-left: 5px solid var(--accent);
      box-shadow: var(--shadow-sm);
    }

    .data-value {
      font-size: 2.5rem;
      font-weight: 800;
      color: var(--primary);
    }

    .data-trend {
      color: var(--accent);
      margin-top: 0.5rem;
      display: flex;
      align-items: center;
      gap: 4px;
    }

    /* 对比 */
    .compare-row {
      display: flex;
      gap: 2rem;
      align-items: stretch;
    }

    .compare-card {
      flex: 1;
      border-radius: 20px;
      padding: 2.5rem;
      background: #EBEEF2;
      color: #4A5B6B;
    }

    .compare-card.highlight {
      background: white;
      border: 2px solid var(--accent);
      color: var(--text-main);
      box-shadow: var(--shadow-hover);
    }

    .compare-list {
      list-style: none;
      margin-top: 1.8rem;
    }

    .compare-list li {
      margin-bottom: 1rem;
      display: flex;
      align-items: center;
      gap: 10px;
    }

    /* FAQ */
    .faq-item {
      background: white;
      border-radius: 14px;
      margin-bottom: 1rem;
      box-shadow: var(--shadow-sm);
    }

    .faq-question {
      width: 100%;
      background: none;
      border: none;
      padding: 1.5rem 1.8rem;
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-weight: 600;
      font-size: 1.1rem;
      cursor: pointer;
    }

    .faq-answer {
      padding: 0 1.8rem 1.5rem;
      display: none;
      color: var(--text-muted);
      line-height: 1.8;
    }

    .faq-item.active .faq-answer {
      display: block;
    }

    .faq-item.active .faq-icon {
      color: var(--secondary);
    }

    /* CTA */
    .cta-section {
      background: linear-gradient(135deg, #0A2E4D 0%, #0A1C2E 100%);
      border-radius: 32px;
      padding: 4rem 2rem;
      text-align: center;
      color: white;
    }

    .cta-form {
      display: flex;
      max-width: 500px;
      margin: 2rem auto 0;
      gap: 12px;
    }

    .cta-input {
      flex: 1;
      padding: 14px 18px;
      border-radius: var(--radius-input);
      border: none;
      background: white;
    }

    .btn-cta {
      background: var(--secondary);
      color: white;
      border: none;
      padding: 14px 28px;
      border-radius: var(--radius-btn);
      font-weight: 700;
      cursor: pointer;
      transition: 0.2s;
    }

    .btn-cta:hover {
      background: #F76B3A;
      transform: scale(1.02);
    }

    .footer {
      background: var(--dark-bg);
      color: #8A9BB0;
      padding: 3rem 0 1.5rem;
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr;
      gap: 2rem;
    }

    .footer a {
      color: #B0C4D9;
    }

    .footer a:hover {
      color: white;
    }

    .copyright {
      text-align: center;
      margin-top: 2.5rem;
      font-size: 0.85rem;
      border-top: 1px solid rgba(255,255,255,0.1);
      padding-top: 1.5rem;
    }

    @media (max-width: 1024px) {
      .cards-grid { grid-template-columns: repeat(2,1fr); }
      .data-grid { grid-template-columns: repeat(2,1fr); }
      .compare-row { flex-direction: column; }
    }

    @media (max-width: 768px) {
      .nav-links { display: none; }
      .menu-toggle { display: block; }
      .hero-grid {
        flex-direction: column;
      }
      .hero-stats {
        grid-template-columns: repeat(2,1fr);
        width: 100%;
      }
      .cards-grid { grid-template-columns: 1fr; }
      .data-grid { grid-template-columns: 1fr; }
      .footer-grid { grid-template-columns: 1fr; }
      .cta-form { flex-direction: column; }
    }