/* roulang page: index */
:root {
      --primary: #4E6EF2;
      --primary-dark: #3B5BDB;
      --accent: #7C3AED;
      --success: #00B578;
      --warning: #FF9F0A;
      --danger: #FA5151;
      --text-primary: #1F2329;
      --text-secondary: #86909C;
      --bg-page: #F5F6FA;
      --bg-card: #FFFFFF;
      --bg-light: #EEF0FE;
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-tag: 20px;
      --shadow-sm: 0 2px 8px rgba(0,0,0,0.04);
      --shadow-md: 0 4px 16px rgba(0,0,0,0.08);
      --shadow-lg: 0 8px 24px rgba(0,0,0,0.12);
      --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
      --max-width: 1200px;
      --header-height: 64px;
      --mobile-bottom-nav-height: 60px;
    }

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

    html {
      scroll-behavior: smooth;
      font-size: 16px;
    }

    body {
      font-family: var(--font-family);
      background-color: var(--bg-page);
      color: var(--text-primary);
      line-height: 1.6;
      -webkit-font-smoothing: antialiased;
      -moz-osx-font-smoothing: grayscale;
      padding-bottom: 0;
    }

    a {
      color: inherit;
      text-decoration: none;
      transition: color 0.15s ease, border-color 0.15s ease;
    }

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

    button, input {
      font-family: inherit;
    }

    .container {
      max-width: var(--max-width);
      margin-left: auto;
      margin-right: auto;
      padding-left: 24px;
      padding-right: 24px;
      width: 100%;
    }

    /* 头部导航 PC */
    .site-header {
      background: var(--bg-card);
      box-shadow: 0 1px 0 rgba(0,0,0,0.04);
      position: sticky;
      top: 0;
      z-index: 100;
      height: var(--header-height);
      display: flex;
      align-items: center;
    }
    .header-inner {
      display: flex;
      justify-content: space-between;
      align-items: center;
      width: 100%;
    }
    .logo {
      display: flex;
      align-items: center;
      gap: 8px;
      font-weight: 700;
      font-size: 20px;
      color: var(--primary);
    }
    .logo-icon {
      width: 32px;
      height: 32px;
      background: linear-gradient(135deg, var(--primary), var(--accent));
      border-radius: 8px;
      display: flex;
      align-items: center;
      justify-content: center;
      color: white;
      font-size: 18px;
    }
    .nav-list {
      display: flex;
      list-style: none;
      gap: 32px;
    }
    .nav-list a {
      font-size: 16px;
      font-weight: 500;
      color: var(--text-primary);
      padding-bottom: 4px;
      border-bottom: 2px solid transparent;
      transition: border-color 0.15s, color 0.15s;
    }
    .nav-list a:hover,
    .nav-list a.active {
      color: var(--primary);
      border-bottom-color: var(--primary);
    }

    /* 底部移动导航 */
    .mobile-bottom-nav {
      display: none;
      position: fixed;
      bottom: 0;
      left: 0;
      width: 100%;
      height: var(--mobile-bottom-nav-height);
      background: var(--bg-card);
      box-shadow: 0 -2px 12px rgba(0,0,0,0.04);
      justify-content: space-around;
      align-items: center;
      z-index: 110;
      padding: 0 16px;
      border-top: 1px solid rgba(0,0,0,0.04);
    }
    .mobile-nav-item {
      display: flex;
      flex-direction: column;
      align-items: center;
      color: var(--text-secondary);
      font-size: 10px;
      font-weight: 500;
      gap: 4px;
      transition: color 0.15s;
    }
    .mobile-nav-item.active {
      color: var(--primary);
    }
    .mobile-nav-icon {
      font-size: 20px;
      width: 24px;
      height: 24px;
      display: flex;
      align-items: center;
      justify-content: center;
    }

    /* 板块通用间距 */
    section {
      padding: 80px 0;
    }

    .section-title {
      font-size: 24px;
      font-weight: 600;
      margin-bottom: 16px;
      color: var(--text-primary);
      text-align: center;
    }
    .section-subtitle {
      font-size: 16px;
      color: var(--text-secondary);
      text-align: center;
      margin-bottom: 48px;
      max-width: 600px;
      margin-left: auto;
      margin-right: auto;
    }

    /* 按钮系统 */
    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      padding: 12px 28px;
      border-radius: var(--radius-btn);
      font-size: 16px;
      font-weight: 600;
      cursor: pointer;
      border: none;
      transition: background 0.2s, transform 0.15s, box-shadow 0.2s;
      text-align: center;
      line-height: 1.2;
    }
    .btn-primary {
      background: var(--primary);
      color: white;
    }
    .btn-primary:hover {
      background: var(--primary-dark);
      transform: scale(1.02);
    }
    .btn-secondary {
      background: #F0F1F5;
      color: var(--primary);
    }
    .btn-secondary:hover {
      background: #E4E6EF;
    }
    .btn-white {
      background: white;
      color: var(--primary);
    }
    .btn-white:hover {
      background: #f0f2ff;
    }

    /* Hero */
    .hero {
      background: var(--bg-page);
      padding: 60px 0 80px;
      display: flex;
      align-items: center;
      min-height: 70vh;
    }
    .hero-grid {
      display: flex;
      align-items: center;
      gap: 40px;
      width: 100%;
    }
    .hero-left {
      flex: 0 0 60%;
    }
    .hero-right {
      flex: 0 0 40%;
      position: relative;
    }
    .hero-bg-visual {
      width: 100%;
      height: 400px;
      background-image: url('/assets/images/backpic/back-1.webp');
      background-size: cover;
      background-position: center;
      border-radius: var(--radius-card);
      position: relative;
      overflow: hidden;
    }
    .hero-bg-visual::after {
      content: '';
      position: absolute;
      inset: 0;
      background: linear-gradient(135deg, rgba(78,110,242,0.15), rgba(124,58,237,0.15));
    }
    .hero-title {
      font-size: 28px;
      font-weight: 700;
      line-height: 1.3;
      margin-bottom: 16px;
      color: var(--text-primary);
    }
    .hero-subtitle {
      font-size: 16px;
      color: var(--text-secondary);
      line-height: 1.5;
      margin-bottom: 32px;
      max-width: 480px;
    }
    .hero-actions {
      display: flex;
      gap: 16px;
      flex-wrap: wrap;
    }

    /* 亮点网格 */
    .highlights-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .highlight-card {
      background: var(--bg-card);
      padding: 24px;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-sm);
      transition: transform 0.2s, box-shadow 0.2s;
    }
    .highlight-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-md);
    }
    .highlight-icon {
      width: 40px;
      height: 40px;
      background: var(--bg-light);
      border-radius: 12px;
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 20px;
      color: var(--primary);
      font-size: 20px;
    }
    .highlight-title {
      font-size: 18px;
      font-weight: 600;
      margin-bottom: 8px;
    }
    .highlight-desc {
      font-size: 14px;
      color: var(--text-secondary);
      line-height: 1.5;
    }

    /* 案例瀑布 */
    .cases-masonry {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 24px;
    }
    .case-card {
      background: var(--bg-card);
      border-radius: var(--radius-card);
      overflow: hidden;
      box-shadow: var(--shadow-sm);
      transition: transform 0.2s, box-shadow 0.2s;
    }
    .case-card:hover {
      transform: translateY(-4px);
      box-shadow: var(--shadow-md);
    }
    .case-img {
      width: 100%;
      height: 200px;
      object-fit: cover;
      background: #e9ebf0;
    }
    .case-body {
      padding: 20px 24px;
    }
    .case-title {
      font-size: 16px;
      font-weight: 600;
      margin-bottom: 8px;
    }
    .case-tag {
      display: inline-block;
      background: var(--bg-light);
      color: var(--primary);
      font-size: 12px;
      font-weight: 500;
      padding: 4px 12px;
      border-radius: var(--radius-tag);
      margin-bottom: 12px;
    }
    .case-desc {
      font-size: 14px;
      color: var(--text-secondary);
    }

    /* 方案对比 */
    .solutions-table {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 24px;
    }
    .solution-card {
      background: var(--bg-card);
      border-radius: var(--radius-card);
      padding: 32px 24px;
      box-shadow: var(--shadow-sm);
      text-align: center;
      transition: transform 0.2s;
      border: 2px solid transparent;
    }
    .solution-card.featured {
      border-color: var(--primary);
      background: #F8FAFF;
      transform: scale(1.02);
      position: relative;
    }
    .solution-badge {
      background: var(--primary);
      color: white;
      font-size: 12px;
      padding: 4px 16px;
      border-radius: var(--radius-tag);
      display: inline-block;
      margin-bottom: 12px;
    }
    .solution-name {
      font-size: 18px;
      font-weight: 600;
      margin-bottom: 20px;
    }
    .solution-features {
      list-style: none;
      text-align: left;
      margin-bottom: 24px;
    }
    .solution-features li {
      font-size: 14px;
      margin-bottom: 12px;
      display: flex;
      align-items: center;
      gap: 8px;
    }

    /* FAQ */
    .faq-list {
      max-width: 800px;
      margin: 0 auto;
    }
    .faq-item {
      border-bottom: 1px solid #E5E6EB;
      padding: 20px 0;
    }
    .faq-question {
      font-size: 16px;
      font-weight: 600;
      color: var(--primary);
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
      user-select: none;
    }
    .faq-icon {
      transition: transform 0.15s ease;
      font-size: 20px;
    }
    .faq-answer {
      font-size: 14px;
      color: var(--text-primary);
      padding-top: 12px;
      display: none;
      line-height: 1.5;
    }
    .faq-item.open .faq-answer {
      display: block;
    }
    .faq-item.open .faq-icon {
      transform: rotate(45deg);
    }

    /* CTA 区 */
    .cta-section {
      background: linear-gradient(135deg, var(--primary), var(--primary-dark));
      color: white;
      text-align: center;
      padding: 80px 0;
    }
    .cta-title {
      font-size: 24px;
      font-weight: 700;
      margin-bottom: 16px;
    }
    .cta-desc {
      font-size: 16px;
      margin-bottom: 32px;
      opacity: 0.9;
    }

    /* 页脚 */
    .site-footer {
      background: var(--bg-page);
      padding: 60px 0 40px;
      font-size: 14px;
    }
    .footer-grid {
      display: grid;
      grid-template-columns: repeat(4, 1fr);
      gap: 24px;
      margin-bottom: 40px;
    }
    .footer-col h4 {
      font-size: 14px;
      font-weight: 600;
      margin-bottom: 16px;
    }
    .footer-col a {
      display: block;
      color: var(--text-secondary);
      margin-bottom: 8px;
    }
    .footer-col a:hover {
      color: var(--primary);
    }
    .newsletter input {
      width: 100%;
      padding: 12px 16px;
      border-radius: var(--radius-tag);
      border: 1px solid #ddd;
      background: white;
    }
    .copyright {
      text-align: center;
      color: var(--text-secondary);
      margin-top: 24px;
      font-size: 14px;
    }

    /* 响应式 */
    @media (max-width: 1024px) {
      .hero-grid {
        flex-direction: column;
      }
      .hero-left, .hero-right {
        flex: 1 1 auto;
        width: 100%;
      }
      .hero-bg-visual {
        height: 280px;
      }
    }
    @media (max-width: 768px) {
      .site-header {
        display: none;
      }
      .mobile-bottom-nav {
        display: flex;
      }
      body {
        padding-bottom: var(--mobile-bottom-nav-height);
      }
      section {
        padding: 48px 0;
      }
      .highlights-grid {
        grid-template-columns: 1fr;
      }
      .cases-masonry {
        grid-template-columns: 1fr;
      }
      .solutions-table {
        grid-template-columns: 1fr;
      }
      .footer-grid {
        grid-template-columns: 1fr 1fr;
      }
      .hero-title {
        font-size: 24px;
      }
      .container {
        padding-left: 16px;
        padding-right: 16px;
      }
    }