/* roulang page: index */
:root {
      --primary: #1A5F7A;
      --primary-deep: #0F3B4F;
      --bg: #F7F9FB;
      --card-bg: #FFFFFF;
      --accent: #E85D3F;
      --accent-hover: #C94A30;
      --success: #2D9C6C;
      --text-main: #1A1A1A;
      --text-desc: #4A4A4A;
      --text-muted: #6B6B6B;
      --border-light: #E8EDF2;
      --shadow-sm: 0 2px 12px rgba(15, 59, 79, 0.06);
      --shadow-md: 0 8px 24px rgba(15, 59, 79, 0.10);
      --radius: 12px;
      --radius-btn: 8px;
      --font-title: 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
      --font-body: 'PingFang SC', 'Microsoft YaHei', 'Noto Sans SC', sans-serif;
      --font-number: 'Inter', 'PingFang SC', sans-serif;
      --transition: 0.25s ease;
    }

    * {
      box-sizing: border-box;
    }

    body {
      font-family: var(--font-body);
      font-size: 16px;
      font-weight: 400;
      line-height: 1.7;
      color: var(--text-main);
      background-color: var(--bg);
      margin: 0;
      padding: 0;
    }

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

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

    h1, h2, h3, h4 {
      font-family: var(--font-title);
      margin: 0 0 20px 0;
    }

    h1 {
      font-size: 42px;
      font-weight: 700;
      line-height: 1.2;
    }
    h2 {
      font-size: 32px;
      font-weight: 700;
    }
    h3 {
      font-size: 20px;
      font-weight: 600;
    }

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

    .section {
      padding: 80px 0;
    }

    /* 导航 */
    .site-header {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 72px;
      background: rgba(247, 249, 251, 0.95);
      backdrop-filter: blur(8px);
      box-shadow: 0 1px 0 rgba(15, 59, 79, 0.08);
      z-index: 100;
      display: flex;
      align-items: center;
    }

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

    .logo {
      font-family: var(--font-title);
      font-size: 24px;
      font-weight: 700;
      color: var(--primary);
      display: flex;
      align-items: center;
      gap: 8px;
    }
    .logo i {
      font-size: 26px;
      color: var(--accent);
    }

    .nav-links {
      display: flex;
      gap: 32px;
      align-items: center;
    }

    .nav-links a {
      font-size: 15px;
      font-weight: 500;
      color: var(--text-desc);
      padding: 6px 0;
      border-bottom: 2px solid transparent;
      transition: var(--transition);
    }

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

    .menu-toggle {
      display: none;
      background: none;
      border: none;
      font-size: 24px;
      color: var(--primary);
      cursor: pointer;
    }

    /* 按钮 */
    .btn {
      display: inline-block;
      padding: 14px 32px;
      border-radius: var(--radius-btn);
      font-weight: 600;
      font-size: 16px;
      transition: var(--transition);
      text-align: center;
      border: 2px solid transparent;
      cursor: pointer;
    }

    .btn-primary {
      background: var(--accent);
      color: white;
      border-color: var(--accent);
    }
    .btn-primary:hover {
      background: var(--accent-hover);
      border-color: var(--accent-hover);
      color: white;
    }

    .btn-outline {
      background: transparent;
      border-color: var(--primary);
      color: var(--primary);
    }
    .btn-outline:hover {
      background: rgba(26, 95, 122, 0.08);
      border-color: var(--primary-deep);
      color: var(--primary-deep);
    }

    .btn-white {
      background: white;
      color: var(--accent);
      border-color: white;
      font-weight: 700;
    }
    .btn-white:hover {
      background: #f0f0f0;
    }

    /* Hero */
    .hero-grid {
      display: grid;
      grid-template-columns: 7fr 5fr;
      gap: 40px;
      align-items: center;
    }
    .hero-stats {
      display: flex;
      gap: 32px;
      margin-top: 32px;
    }
    .stat-item {
      font-family: var(--font-number);
    }
    .stat-number {
      font-size: 28px;
      font-weight: 700;
      color: var(--accent);
    }
    .stat-label {
      font-size: 14px;
      color: var(--text-muted);
    }
    .hero-image {
      background: url('/assets/images/backpic/back-1.webp') center/cover no-repeat;
      border-radius: var(--radius);
      box-shadow: var(--shadow-md);
      min-height: 380px;
    }

    /* 卡片 */
    .card {
      background: var(--card-bg);
      border-radius: var(--radius);
      box-shadow: var(--shadow-sm);
      padding: 28px;
      border: 1px solid var(--border-light);
      transition: var(--transition);
      height: 100%;
    }
    .card:hover {
      box-shadow: var(--shadow-md);
      transform: translateY(-2px);
    }

    .icon-circle {
      width: 64px;
      height: 64px;
      background: rgba(26, 95, 122, 0.08);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 28px;
      color: var(--primary);
      margin-bottom: 24px;
    }

    .grid-3 {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 30px;
    }
    .grid-2 {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 30px;
    }

    /* 产品卡片 */
    .product-card {
      display: flex;
      background: var(--card-bg);
      border-radius: var(--radius);
      box-shadow: var(--shadow-sm);
      border: 1px solid var(--border-light);
      overflow: hidden;
    }
    .product-img {
      width: 40%;
      background-size: cover;
      background-position: center;
    }
    .product-body {
      padding: 28px;
      width: 60%;
    }
    .feature-list {
      list-style: none;
      padding: 0;
      margin: 16px 0;
    }
    .feature-list li {
      margin-bottom: 10px;
      color: var(--text-desc);
      font-size: 15px;
      display: flex;
      align-items: flex-start;
      gap: 8px;
    }
    .feature-list i {
      color: var(--success);
      font-size: 16px;
      margin-top: 4px;
    }

    /* 场景卡片 */
    .scene-card {
      border-radius: var(--radius);
      overflow: hidden;
      background: var(--card-bg);
      box-shadow: var(--shadow-sm);
    }
    .scene-img {
      height: 200px;
      background-size: cover;
      background-position: center;
    }
    .scene-text {
      padding: 20px 28px 28px;
    }

    /* 案例 */
    .case-card {
      background: #FAFBFD;
      border-radius: var(--radius);
      padding: 28px;
      border: 1px solid var(--border-light);
    }
    .case-badge {
      background: rgba(232, 93, 63, 0.12);
      color: var(--accent);
      font-size: 13px;
      font-weight: 600;
      padding: 4px 12px;
      border-radius: 20px;
      display: inline-block;
    }
    .case-number {
      font-size: 48px;
      font-weight: 700;
      color: var(--success);
      font-family: var(--font-number);
    }

    /* 价格 */
    .pricing-card {
      position: relative;
      background: var(--card-bg);
      border-radius: var(--radius);
      padding: 32px 28px;
      border: 2px solid var(--border-light);
      transition: var(--transition);
    }
    .pricing-card.popular {
      border-color: var(--accent);
      box-shadow: 0 8px 28px rgba(232, 93, 63, 0.12);
    }
    .popular-badge {
      position: absolute;
      top: -14px;
      left: 50%;
      transform: translateX(-50%);
      background: var(--accent);
      color: white;
      font-size: 14px;
      font-weight: 600;
      padding: 4px 20px;
      border-radius: 20px;
    }
    .price {
      font-size: 48px;
      font-weight: 700;
      font-family: var(--font-number);
      color: var(--primary-deep);
    }

    /* FAQ */
    .accordion-title {
      font-size: 18px;
      font-weight: 500;
      color: var(--text-main);
      border-bottom: 1px solid var(--border-light);
      padding: 18px 0;
      cursor: pointer;
      transition: var(--transition);
    }
    .accordion-title:hover,
    .accordion-title.is-active {
      color: var(--primary);
    }
    .accordion-content {
      padding: 12px 0 24px;
      color: var(--text-desc);
      font-size: 15px;
      display: none;
      border-bottom: 1px solid var(--border-light);
    }
    .accordion-content.is-active {
      display: block;
    }

    /* CTA */
    .cta-section {
      background: linear-gradient(135deg, #1A5F7A 0%, #0F3B4F 100%);
      color: white;
      text-align: center;
    }

    /* 页脚 */
    .footer-grid {
      display: grid;
      grid-template-columns: 2fr 1.5fr 1.5fr 1.5fr;
      gap: 30px;
    }
    .footer {
      background: #0F3B4F;
      color: #B0C4D0;
      padding: 60px 0 30px;
    }
    .footer a {
      color: #B0C4D0;
    }
    .footer a:hover {
      color: white;
    }
    .social-icons i {
      font-size: 20px;
      width: 40px;
      height: 40px;
      border: 1px solid #B0C4D0;
      border-radius: 50%;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      margin-right: 10px;
      transition: var(--transition);
    }
    .social-icons i:hover {
      background: white;
      color: #0F3B4F;
    }

    @media (max-width: 1024px) {
      .hero-grid {
        grid-template-columns: 1fr 1fr;
      }
    }

    @media (max-width: 768px) {
      h1 { font-size: 30px; }
      h2 { font-size: 26px; }
      .section { padding: 50px 0; }
      .nav-links {
        display: none;
        position: absolute;
        top: 72px;
        left: 0;
        width: 100%;
        background: white;
        flex-direction: column;
        padding: 20px;
        box-shadow: var(--shadow-md);
      }
      .nav-links.active {
        display: flex;
      }
      .menu-toggle {
        display: block;
      }
      .hero-grid {
        grid-template-columns: 1fr;
      }
      .hero-image {
        min-height: 260px;
      }
      .grid-3, .grid-2, .footer-grid {
        grid-template-columns: 1fr;
      }
      .product-card {
        flex-direction: column;
      }
      .product-img {
        width: 100%;
        height: 200px;
      }
      .product-body {
        width: 100%;
      }
    }