/* roulang page: index */
/* ========== 设计变量与全局重置 ========== */
    :root {
      --primary: #1B7E3D;
      --primary-hover: #15632F;
      --accent: #F15A24;
      --accent-hover: #D94A1A;
      --bg: #F7F8F4;
      --card-bg: #FFFFFF;
      --text: #2D2D2D;
      --text-secondary: #6B6B6B;
      --border: #E0E2DB;
      --shadow-sm: 0 2px 12px rgba(0,0,0,0.06);
      --shadow-md: 0 6px 20px rgba(0,0,0,0.10);
      --radius-card: 12px;
      --radius-btn: 8px;
      --radius-input: 6px;
      --radius-capsule: 40px;
      --font-body: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", "Helvetica Neue", Arial, sans-serif;
      --font-number: "DIN Alternate", "PingFang SC", sans-serif;
      --max-width: 1200px;
      --section-gap: 100px;
    }
    
    * {
      box-sizing: border-box;
    }
    
    body {
      font-family: var(--font-body);
      background-color: var(--bg);
      color: var(--text);
      line-height: 1.6;
      margin: 0;
      padding: 0;
      -webkit-font-smoothing: antialiased;
    }
    
    /* 容器自定义宽度 */
    .custom-container {
      max-width: var(--max-width);
      margin: 0 auto;
      padding: 0 20px;
    }
    
    /* 段落最大宽度 */
    .text-block {
      max-width: 680px;
      margin-left: auto;
      margin-right: auto;
    }
    
    /* H2 标题样式 */
    h2.section-title {
      font-size: 28px;
      font-weight: 600;
      color: var(--text);
      margin-bottom: 40px;
      text-align: center;
      position: relative;
    }
    h2.section-title::after {
      content: '';
      display: block;
      width: 40px;
      height: 3px;
      background-color: var(--primary);
      margin: 12px auto 0;
      border-radius: 2px;
    }
    
    /* 按钮系统 */
    .btn-primary {
      background-color: var(--primary);
      color: white;
      border-radius: var(--radius-btn);
      padding: 12px 28px;
      font-weight: 600;
      display: inline-block;
      transition: background-color 0.2s ease;
      border: none;
      cursor: pointer;
      text-decoration: none;
      min-width: 44px;
      min-height: 44px;
      line-height: 1.2;
      text-align: center;
    }
    .btn-primary:hover {
      background-color: var(--primary-hover);
      color: white;
      text-decoration: none;
    }
    
    .btn-secondary {
      background: transparent;
      color: var(--primary);
      border: 2px solid var(--primary);
      border-radius: var(--radius-btn);
      padding: 10px 26px;
      font-weight: 600;
      display: inline-block;
      transition: all 0.2s ease;
      text-decoration: none;
      cursor: pointer;
      min-width: 44px;
      min-height: 44px;
      line-height: 1.2;
      text-align: center;
    }
    .btn-secondary:hover {
      background-color: var(--primary);
      color: white;
      text-decoration: none;
    }
    
    .btn-accent {
      background-color: var(--accent);
      color: white;
      border-radius: var(--radius-btn);
      padding: 12px 28px;
      font-weight: 600;
      display: inline-block;
      transition: background-color 0.2s ease;
      border: none;
      cursor: pointer;
      text-decoration: none;
      min-width: 44px;
      min-height: 44px;
    }
    .btn-accent:hover {
      background-color: var(--accent-hover);
      color: white;
      text-decoration: none;
    }
    
    /* 卡片系统 */
    .custom-card {
      background: var(--card-bg);
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-sm);
      padding: 28px 24px;
      transition: box-shadow 0.25s ease, transform 0.2s ease;
      border-top: 4px solid var(--primary);
      height: 100%;
    }
    .custom-card:hover {
      box-shadow: var(--shadow-md);
      transform: translateY(-3px);
    }
    .card-icon-circle {
      width: 48px;
      height: 48px;
      background-color: #E8F0E9;
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      margin-bottom: 20px;
      color: var(--primary);
      font-size: 24px;
    }
    .card-link {
      color: var(--primary);
      font-weight: 600;
      text-decoration: none;
      display: inline-flex;
      align-items: center;
      gap: 6px;
      margin-top: 16px;
    }
    .card-link:hover {
      text-decoration: underline;
    }
    
    /* 案例卡片悬停浮层 */
    .case-card {
      position: relative;
      overflow: hidden;
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-sm);
      background: var(--card-bg);
      transition: all 0.25s ease;
      height: 100%;
    }
    .case-card:hover {
      box-shadow: var(--shadow-md);
    }
    .case-img {
      width: 100%;
      aspect-ratio: 16 / 9;
      object-fit: cover;
      display: block;
      transition: transform 0.3s ease;
      background-color: #E8ECDF;
    }
    .case-card:hover .case-img {
      transform: scale(1.03);
    }
    .case-overlay {
      position: absolute;
      top: 0;
      left: 0;
      right: 0;
      background: rgba(0,0,0,0.7);
      color: white;
      padding: 8px 16px;
      font-size: 14px;
      opacity: 0;
      transition: opacity 0.25s ease;
      display: flex;
      align-items: center;
      justify-content: center;
      pointer-events: none;
    }
    .case-card:hover .case-overlay {
      opacity: 1;
    }
    
    /* 导航胶囊 */
    .capsule-nav {
      position: fixed;
      top: 16px;
      left: 50%;
      transform: translateX(-50%);
      background: rgba(255,255,255,0.96);
      backdrop-filter: blur(8px);
      border-radius: var(--radius-capsule);
      box-shadow: 0 2px 16px rgba(0,0,0,0.08);
      padding: 8px 24px;
      z-index: 999;
      display: flex;
      align-items: center;
      gap: 32px;
      white-space: nowrap;
    }
    .nav-logo {
      font-weight: 700;
      font-size: 18px;
      color: var(--primary);
      text-decoration: none;
      pointer-events: none;
    }
    .nav-link {
      color: var(--text);
      font-weight: 500;
      font-size: 15px;
      text-decoration: none;
      padding-bottom: 4px;
      border-bottom: 2px solid transparent;
      transition: color 0.2s, border-color 0.2s;
    }
    .nav-link:hover {
      color: var(--primary);
    }
    .nav-link.active {
      color: var(--primary);
      border-bottom-color: var(--primary);
      width: fit-content;
    }
    
    /* 移动端导航 */
    .mobile-nav-toggle {
      display: none;
      background: none;
      border: none;
      font-size: 24px;
      color: var(--primary);
      cursor: pointer;
    }
    
    /* 数据优势数字 */
    .stat-number {
      font-family: var(--font-number);
      font-size: 42px;
      font-weight: 700;
      color: var(--accent);
      letter-spacing: 0.5px;
      line-height: 1.1;
    }
    .stat-label {
      color: var(--text-secondary);
      font-size: 16px;
      margin-top: 8px;
    }
    .stat-decor {
      width: 20px;
      height: 3px;
      background-color: var(--primary);
      margin-bottom: 12px;
    }
    
    /* 方案卡片 */
    .solution-card {
      background: var(--card-bg);
      border-radius: var(--radius-card);
      padding: 32px 28px;
      box-shadow: var(--shadow-sm);
      border: 2px solid transparent;
      transition: all 0.25s;
      height: 100%;
      position: relative;
    }
    .solution-card.featured {
      border-color: var(--primary);
    }
    .badge-recommend {
      background: var(--accent);
      color: white;
      font-size: 13px;
      font-weight: 600;
      padding: 4px 14px;
      border-radius: 20px;
      position: absolute;
      top: -12px;
      right: 20px;
    }
    
    /* FAQ */
    .faq-item {
      border-bottom: 1px solid var(--border);
      padding: 18px 0;
      cursor: pointer;
    }
    .faq-question {
      font-weight: 600;
      font-size: 18px;
      display: flex;
      justify-content: space-between;
      align-items: center;
      color: var(--text);
      gap: 16px;
    }
    .faq-question .faq-icon {
      color: var(--accent);
      font-size: 20px;
      transition: transform 0.2s;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease;
      color: var(--text-secondary);
      font-size: 16px;
      padding-top: 0;
    }
    .faq-item.open .faq-answer {
      max-height: 200px;
      padding-top: 12px;
    }
    .faq-item.open .faq-icon {
      transform: rotate(45deg);
    }
    .faq-left-bar {
      width: 4px;
      height: 24px;
      background-color: var(--primary);
      border-radius: 2px;
      margin-right: 12px;
    }
    
    /* 表单 */
    .contact-form input,
    .contact-form textarea {
      border-radius: var(--radius-input);
      border: 1px solid var(--border);
      padding: 12px 16px;
      font-family: var(--font-body);
      transition: border-color 0.2s;
      width: 100%;
    }
    .contact-form input:focus,
    .contact-form textarea:focus {
      border-color: var(--primary);
      outline: none;
    }
    
    /* 页脚 */
    .site-footer {
      background: #2D2D2D;
      color: #B0B0B0;
      padding: 32px 0;
      font-size: 15px;
    }
    .site-footer a {
      color: #B0B0B0;
      text-decoration: none;
      margin-left: 24px;
    }
    .site-footer a:hover {
      text-decoration: underline;
    }
    
    /* 响应式 */
    @media (max-width: 1024px) {
      .capsule-nav {
        gap: 20px;
        padding: 8px 18px;
      }
    }
    @media (max-width: 768px) {
      :root {
        --section-gap: 60px;
      }
      h2.section-title {
        font-size: 22px;
      }
      .capsule-nav {
        top: auto;
        bottom: 16px;
        left: 16px;
        right: 16px;
        transform: none;
        justify-content: space-between;
        border-radius: 30px;
        padding: 8px 20px;
      }
      .nav-links-desktop {
        display: none;
      }
      .mobile-nav-toggle {
        display: block;
      }
      .mobile-menu {
        display: none;
        position: absolute;
        bottom: 70px;
        left: 16px;
        right: 16px;
        background: white;
        border-radius: 28px;
        box-shadow: var(--shadow-md);
        padding: 16px;
        flex-direction: column;
        gap: 12px;
      }
      .mobile-menu.active {
        display: flex;
      }
      .hero-image {
        margin-top: 32px;
      }
      .btn-primary, .btn-secondary {
        width: 100%;
        margin-bottom: 12px;
      }
      .stat-number {
        font-size: 32px;
      }
    }
    @media (max-width: 480px) {
      .custom-container {
        padding: 0 16px;
      }
    }