/* roulang page: index */
:root {
      --primary-dark: #1E1E24;
      --accent-purple: #7B2FF7;
      --accent-cyan: #00E5A0;
      --bg-cool: #F7F8FC;
      --text-main: #1E1E24;
      --text-soft: #6B7280;
      --border-light: #E5E7EB;
      --card-shadow: 0 4px 20px rgba(0,0,0,0.06);
      --card-hover-shadow: 0 8px 30px rgba(0,0,0,0.12);
      --radius-sm: 8px;
      --radius-md: 12px;
      --radius-lg: 16px;
      --transition: 0.3s ease;
    }

    * {
      box-sizing: border-box;
    }

    body {
      font-family: -apple-system, "Helvetica Neue", "PingFang SC", "Microsoft YaHei", sans-serif;
      background-color: var(--bg-cool);
      color: var(--text-main);
      line-height: 1.6;
      margin: 0;
      font-size: 16px;
      font-weight: 400;
    }

    h1, h2, h3, h4 {
      font-weight: 700;
      margin-top: 0;
    }

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

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

    button, .button {
      font-family: inherit;
      cursor: pointer;
      border: none;
      outline: none;
      transition: all var(--transition);
    }

    input, select, textarea {
      font-family: inherit;
      outline: none;
      transition: border var(--transition), box-shadow var(--transition);
    }

    .container {
      max-width: 1200px;
      margin: 0 auto;
      padding: 0 20px;
    }

    /* 导航 */
    .site-header {
      background: #fff;
      box-shadow: 0 2px 12px rgba(0,0,0,0.04);
      height: 64px;
      display: flex;
      align-items: center;
      position: sticky;
      top: 0;
      z-index: 100;
    }

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

    .logo {
      font-size: 20px;
      font-weight: 700;
      color: var(--primary-dark);
      display: flex;
      align-items: center;
      gap: 8px;
    }

    .logo i {
      color: var(--accent-purple);
      font-size: 24px;
    }

    .nav-links {
      display: flex;
      gap: 28px;
      align-items: center;
    }

    .nav-links a {
      font-size: 15px;
      font-weight: 500;
      color: var(--text-main);
      position: relative;
    }

    .nav-links a:hover,
    .nav-links a.active {
      color: var(--accent-purple);
    }

    .search-box {
      display: flex;
      align-items: center;
      background: #f3f4f6;
      border-radius: 30px;
      padding: 6px 14px;
      gap: 6px;
    }

    .search-box input {
      border: none;
      background: transparent;
      font-size: 14px;
      width: 120px;
    }

    .btn-primary {
      background: var(--accent-purple);
      color: #fff;
      border-radius: var(--radius-sm);
      padding: 10px 24px;
      font-weight: 600;
      font-size: 15px;
      white-space: nowrap;
    }

    .btn-primary:hover {
      background: #6518E0;
    }

    .btn-outline {
      background: transparent;
      border: 1px solid var(--primary-dark);
      color: var(--primary-dark);
      border-radius: var(--radius-sm);
      padding: 10px 24px;
      font-weight: 600;
      font-size: 15px;
    }

    .btn-outline:hover {
      background: rgba(0,0,0,0.04);
    }

    .hamburger {
      display: none;
      font-size: 24px;
      cursor: pointer;
    }

    /* Hero */
    #hero {
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      position: relative;
      padding: 100px 0;
      color: #fff;
    }

    #hero::before {
      content: '';
      position: absolute;
      inset: 0;
      background: linear-gradient(135deg, rgba(30,30,36,0.85) 0%, rgba(30,30,36,0.7) 100%);
    }

    .hero-grid {
      display: flex;
      align-items: center;
      gap: 60px;
      position: relative;
      z-index: 2;
    }

    .hero-text {
      flex: 1;
    }

    .hero-text h1 {
      font-size: 48px;
      font-weight: 700;
      line-height: 1.2;
      margin-bottom: 16px;
      animation: fadeUp 0.8s ease;
    }

    .hero-sub {
      font-size: 20px;
      margin-bottom: 32px;
      opacity: 0.9;
    }

    .hero-buttons {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }

    .hero-visual {
      flex: 1;
      background: rgba(255,255,255,0.08);
      backdrop-filter: blur(8px);
      border-radius: var(--radius-md);
      padding: 24px;
      border: 1px solid rgba(255,255,255,0.15);
      color: #fff;
    }

    .data-stream {
      display: flex;
      flex-direction: column;
      gap: 14px;
    }

    .data-item {
      display: flex;
      justify-content: space-between;
      font-size: 15px;
      border-bottom: 1px solid rgba(255,255,255,0.2);
      padding-bottom: 6px;
    }

    @keyframes fadeUp {
      0% { opacity: 0; transform: translateY(20px); }
      100% { opacity: 1; transform: translateY(0); }
    }

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

    .section-title {
      font-size: 36px;
      font-weight: 700;
      margin-bottom: 16px;
      color: var(--primary-dark);
    }

    .section-lead {
      font-size: 18px;
      color: var(--text-soft);
      margin-bottom: 48px;
    }

    /* 指标卡 */
    .metrics-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
    }

    .metric-card {
      background: #fff;
      border-radius: var(--radius-md);
      padding: 28px 20px;
      box-shadow: var(--card-shadow);
      transition: var(--transition);
      text-align: center;
    }

    .metric-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--card-hover-shadow);
    }

    .metric-number {
      font-size: 42px;
      font-weight: 800;
      color: var(--accent-cyan);
      font-variant-numeric: tabular-nums;
    }

    .metric-label {
      font-size: 14px;
      color: var(--text-soft);
      margin-top: 8px;
    }

    .trend-up {
      color: var(--accent-cyan);
      font-size: 18px;
      margin-left: 4px;
    }

    /* 服务网格 2x3 不对称 */
    .services-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr;
      gap: 24px;
    }

    .service-card {
      background: #fff;
      border-radius: var(--radius-md);
      padding: 32px 24px;
      box-shadow: var(--card-shadow);
      transition: var(--transition);
      display: flex;
      flex-direction: column;
    }

    .service-card.featured {
      grid-column: span 1;
    }

    .service-card:hover {
      transform: translateY(-5px);
      box-shadow: var(--card-hover-shadow);
    }

    .service-icon {
      font-size: 32px;
      color: var(--accent-purple);
      margin-bottom: 20px;
    }

    .service-card h3 {
      font-size: 20px;
      font-weight: 600;
      margin-bottom: 10px;
    }

    .service-desc {
      font-size: 14px;
      color: var(--text-soft);
      margin-bottom: 18px;
      flex: 1;
    }

    .service-link {
      font-weight: 600;
      color: var(--accent-purple);
      display: flex;
      align-items: center;
      gap: 6px;
    }

    /* 对比 */
    .compare-wrapper {
      display: flex;
      gap: 30px;
      align-items: stretch;
    }

    .compare-col {
      flex: 1;
      background: #fff;
      border-radius: var(--radius-md);
      padding: 32px;
      box-shadow: var(--card-shadow);
    }

    .compare-col.bad {
      border-left: 4px solid #ef4444;
    }

    .compare-col.good {
      border-left: 4px solid var(--accent-cyan);
    }

    .compare-item {
      display: flex;
      align-items: center;
      gap: 12px;
      padding: 12px 0;
      border-bottom: 1px solid var(--border-light);
      font-size: 16px;
    }

    /* FAQ */
    .accordion-title {
      font-size: 18px;
      font-weight: 500;
      background: #fff;
      padding: 16px 20px;
      border-radius: var(--radius-sm);
      margin-bottom: 8px;
      cursor: pointer;
      transition: var(--transition);
      display: flex;
      justify-content: space-between;
      align-items: center;
    }

    .accordion-title i {
      transition: transform 0.3s;
    }

    .accordion-title.active {
      color: var(--accent-purple);
    }

    .accordion-title.active i {
      transform: rotate(45deg);
    }

    .accordion-content {
      background: #f3f4f6;
      border-radius: 0 0 var(--radius-sm) var(--radius-sm);
      padding: 0 20px;
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease, padding 0.3s;
    }

    .accordion-content.open {
      max-height: 200px;
      padding: 16px 20px;
    }

    /* 表单 */
    #contact {
      background: var(--primary-dark);
      color: #fff;
    }

    .contact-form {
      max-width: 600px;
      margin: 0 auto;
    }

    .form-input {
      width: 100%;
      padding: 12px 16px;
      border-radius: 6px;
      border: 1px solid #ccc;
      background: #fff;
      margin-bottom: 16px;
    }

    .form-input:focus {
      border-color: var(--accent-purple);
      box-shadow: 0 0 0 3px rgba(123,47,247,0.2);
    }

    .btn-full {
      width: 100%;
      background: var(--accent-purple);
      color: #fff;
      padding: 14px;
      font-size: 18px;
      font-weight: 600;
      border-radius: var(--radius-sm);
    }

    /* 页脚 */
    .site-footer {
      background: var(--primary-dark);
      color: #ddd;
      padding: 60px 0 30px;
    }

    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1fr 1fr 1fr;
      gap: 40px;
    }

    .footer-logo {
      font-size: 20px;
      font-weight: 700;
      color: #fff;
    }

    .footer-links a {
      display: block;
      margin-bottom: 8px;
      color: #bbb;
    }

    .footer-links a:hover {
      color: var(--accent-cyan);
    }

    .copyright {
      text-align: center;
      margin-top: 40px;
      color: #888;
    }

    /* 移动端 */
    @media (max-width: 1024px) {
      .hero-grid {
        flex-direction: column;
      }
      .metrics-grid {
        grid-template-columns: repeat(2, 1fr);
      }
      .services-grid {
        grid-template-columns: 1fr 1fr;
      }
    }

    @media (max-width: 768px) {
      .nav-links, .search-box {
        display: none;
      }
      .hamburger {
        display: block;
      }
      .hero-text h1 {
        font-size: 36px;
      }
      .services-grid {
        grid-template-columns: 1fr;
      }
      .compare-wrapper {
        flex-direction: column;
      }
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
    }