/* roulang page: index */
:root {
      --primary: #E63946;
      --primary-dark: #C62828;
      --secondary: #1D3557;
      --secondary-light: #2B4C7E;
      --bg: #FAFAFA;
      --card-bg: #FFFFFF;
      --light-pink: #FFF5F5;
      --gray-50: #F5F5F5;
      --gray-100: #E8E8E8;
      --text: #1E1E1E;
      --text-soft: #555555;
      --text-light: #777777;
      --white: #FFFFFF;
      --border-subtle: rgba(0,0,0,0.06);
      --shadow-card: 0 4px 20px rgba(0,0,0,0.04);
      --shadow-hover: 0 12px 32px rgba(0,0,0,0.08);
      --radius-sm: 8px;
      --radius-md: 12px;
      --radius-lg: 16px;
      --font-sans: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", "Inter", "Roboto", system-ui, sans-serif;
      --transition: 0.25s ease;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    html {
      scroll-behavior: smooth;
    }
    body {
      font-family: var(--font-sans);
      background-color: var(--bg);
      color: var(--text);
      line-height: 1.8;
      font-weight: 400;
      font-size: 16px;
      -webkit-font-smoothing: antialiased;
    }
    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
    }
    img {
      max-width: 100%;
      display: block;
      height: auto;
    }
    a {
      text-decoration: none;
      color: inherit;
      transition: var(--transition);
    }
    button, .btn {
      cursor: pointer;
      font-family: inherit;
      border: none;
      background: none;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      font-weight: 600;
      font-size: 16px;
      transition: var(--transition);
      border-radius: var(--radius-sm);
      padding: 14px 32px;
      line-height: 1.2;
    }
    .btn-primary {
      background-color: var(--primary);
      color: var(--white);
      box-shadow: 0 2px 8px rgba(230,57,70,0.2);
    }
    .btn-primary:hover {
      background-color: var(--primary-dark);
      transform: translateY(-1px);
      box-shadow: 0 8px 20px rgba(230,57,70,0.3);
    }
    .btn-outline {
      border: 2px solid var(--secondary);
      color: var(--secondary);
      background: transparent;
    }
    .btn-outline:hover {
      background-color: var(--secondary);
      color: var(--white);
      border-color: var(--secondary);
    }
    .btn-white {
      background: var(--white);
      color: var(--secondary);
      font-weight: 700;
    }
    .btn-white:hover {
      background: #f0f0f0;
      transform: translateY(-1px);
    }

    /* 导航 */
    header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      background: rgba(255,255,255,0.92);
      backdrop-filter: blur(12px);
      height: 72px;
      display: flex;
      align-items: center;
      z-index: 1000;
      border-bottom: 1px solid var(--border-subtle);
      box-shadow: 0 2px 10px rgba(0,0,0,0.02);
    }
    .nav-container {
      display: flex;
      align-items: center;
      justify-content: space-between;
      width: 100%;
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
    }
    .logo {
      display: flex;
      align-items: center;
      gap: 10px;
      font-weight: 800;
      font-size: 24px;
      color: var(--secondary);
      letter-spacing: 1px;
    }
    .logo i {
      color: var(--primary);
      font-size: 28px;
    }
    .nav-links {
      display: flex;
      align-items: center;
      gap: 32px;
    }
    .nav-links a {
      font-weight: 500;
      color: var(--text-soft);
      position: relative;
      padding: 8px 0;
    }
    .nav-links a::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--primary);
      transition: width 0.25s ease;
    }
    .nav-links a:hover {
      color: var(--primary);
    }
    .nav-links a:hover::after {
      width: 100%;
    }
    .nav-cta {
      background: var(--primary);
      color: white;
      padding: 10px 24px;
      border-radius: var(--radius-sm);
      font-weight: 600;
      margin-left: 16px;
    }
    .nav-cta:hover {
      background: var(--primary-dark);
    }
    .hamburger {
      display: none;
      font-size: 26px;
      color: var(--secondary);
      cursor: pointer;
    }
    .mobile-menu {
      display: none;
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100vh;
      background: rgba(255,255,255,0.98);
      backdrop-filter: blur(16px);
      flex-direction: column;
      align-items: center;
      justify-content: center;
      gap: 40px;
      z-index: 999;
      font-size: 22px;
      font-weight: 500;
    }
    .mobile-menu.active {
      display: flex;
    }
    .mobile-menu a {
      color: var(--secondary);
      border-bottom: 2px solid transparent;
      padding-bottom: 4px;
    }
    .mobile-menu a:hover {
      border-bottom-color: var(--primary);
    }

    /* Hero 双栏 */
    .hero {
      padding: 140px 0 100px;
      background: var(--white);
    }
    .hero-grid {
      display: grid;
      grid-template-columns: 55% 45%;
      gap: 60px;
      align-items: center;
    }
    .hero-left h1 {
      font-size: clamp(40px, 5vw, 56px);
      font-weight: 800;
      line-height: 1.2;
      color: var(--secondary);
      margin-bottom: 20px;
    }
    .hero-left h1 span {
      color: var(--primary);
    }
    .hero-sub {
      font-size: 18px;
      color: var(--text-soft);
      margin-bottom: 36px;
      max-width: 480px;
    }
    .hero-buttons {
      display: flex;
      gap: 20px;
      flex-wrap: wrap;
    }
    .hero-right img {
      width: 100%;
      border-radius: var(--radius-lg);
      box-shadow: var(--shadow-hover);
      transition: transform 0.4s ease;
      object-fit: cover;
    }
    .hero-right img:hover {
      transform: scale(1.02);
    }

    /* 板块通用 */
    section {
      padding: 100px 0;
    }
    .section-title {
      font-size: clamp(32px, 4vw, 40px);
      font-weight: 700;
      color: var(--secondary);
      margin-bottom: 16px;
      text-align: center;
    }
    .section-sub {
      color: var(--text-soft);
      text-align: center;
      max-width: 640px;
      margin: 0 auto 56px;
      font-size: 17px;
    }

    /* 亮点网格 */
    .highlight-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
      background: var(--light-pink);
      padding: 60px 0;
      margin-top: -40px;
      border-radius: var(--radius-lg);
    }
    .highlight-card {
      background: var(--white);
      padding: 32px 24px;
      border-radius: var(--radius-md);
      text-align: center;
      box-shadow: var(--shadow-card);
      transition: var(--transition);
    }
    .highlight-card:hover {
      transform: translateY(-6px);
      box-shadow: var(--shadow-hover);
    }
    .highlight-icon {
      font-size: 36px;
      color: var(--primary);
      margin-bottom: 20px;
      transition: 0.2s;
    }
    .highlight-card:hover .highlight-icon {
      color: var(--white);
      background: var(--primary);
      border-radius: 50%;
      padding: 12px;
      display: inline-flex;
    }
    .highlight-card h3 {
      font-size: 22px;
      font-weight: 700;
      margin-bottom: 12px;
      color: var(--secondary);
    }

    /* 案例瀑布流 */
    .cases-masonry {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 28px;
      align-items: start;
    }
    .case-card {
      background: var(--white);
      border-radius: var(--radius-md);
      overflow: hidden;
      box-shadow: var(--shadow-card);
      transition: var(--transition);
    }
    .case-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-hover);
    }
    .case-card img {
      width: 100%;
      height: 200px;
      object-fit: cover;
    }
    .case-info {
      padding: 24px;
    }
    .case-tag {
      display: inline-block;
      background: var(--light-pink);
      color: var(--primary);
      font-weight: 600;
      font-size: 13px;
      padding: 4px 12px;
      border-radius: 20px;
      margin-bottom: 12px;
    }

    /* 方案对比 */
    .compare-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .compare-col {
      background: var(--gray-50);
      border-radius: var(--radius-lg);
      padding: 40px 28px;
      text-align: center;
      transition: var(--transition);
    }
    .compare-col.featured {
      background: var(--secondary);
      color: white;
      transform: scale(1.03);
      box-shadow: var(--shadow-hover);
    }
    .compare-col h3 {
      font-size: 26px;
      margin-bottom: 20px;
    }
    .compare-list {
      list-style: none;
      text-align: left;
      margin: 32px 0;
    }
    .compare-list li {
      padding: 10px 0;
      border-bottom: 1px solid rgba(0,0,0,0.05);
    }

    /* 数据 */
    .stats-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 32px;
      text-align: center;
    }
    .stat-number {
      font-size: 48px;
      font-weight: 800;
      color: var(--primary);
    }

    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
      background: var(--gray-50);
      padding: 24px;
      border-radius: var(--radius-lg);
    }
    .faq-item {
      background: var(--white);
      border-radius: var(--radius-md);
      margin-bottom: 12px;
      box-shadow: var(--shadow-card);
    }
    .faq-question {
      padding: 20px 24px;
      font-weight: 700;
      display: flex;
      justify-content: space-between;
      cursor: pointer;
      font-size: 18px;
    }
    .faq-answer {
      padding: 0 24px 20px;
      display: none;
      color: var(--text-soft);
    }
    .faq-item.active .faq-answer {
      display: block;
    }

    /* CTA */
    .cta-band {
      background: var(--secondary);
      padding: 80px 0;
      text-align: center;
      color: white;
    }
    .cta-buttons {
      display: flex;
      gap: 24px;
      justify-content: center;
      margin-top: 32px;
    }

    /* 页脚 */
    footer {
      background: #0F2440;
      color: #ccc;
      padding: 70px 0 30px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
    }

    @media (max-width: 1024px) {
      .hero-grid, .cases-masonry, .compare-grid {
        grid-template-columns: 1fr 1fr;
      }
      .highlight-grid { grid-template-columns: repeat(2,1fr); }
      .stats-grid { grid-template-columns: repeat(2,1fr); }
    }
    @media (max-width: 768px) {
      .nav-links { display: none; }
      .hamburger { display: block; }
      .hero-grid, .cases-masonry, .compare-grid, .highlight-grid, .footer-grid {
        grid-template-columns: 1fr;
      }
      .hero { padding: 100px 0 60px; }
    }