/* roulang page: index */
:root {
      --primary: #0B1D3A;
      --primary-light: #162D50;
      --accent: #FF6B35;
      --accent-light: #FF8255;
      --bg: #F5F7FB;
      --text-main: #1A1A2E;
      --text-dim: #5A6070;
      --glass-bg: rgba(255,255,255,0.05);
      --glass-border: rgba(255,255,255,0.15);
      --card-shadow: 0 4px 20px rgba(0,0,0,0.06);
      --card-hover-shadow: 0 12px 30px rgba(0,0,0,0.12);
      --glow: 0 0 20px rgba(255,107,53,0.5);
      --glow-hover: 0 0 30px rgba(255,107,53,0.7);
      --radius-card: 16px;
      --radius-btn: 12px;
      --radius-input: 8px;
    }

    * {
      box-sizing: border-box;
    }

    body {
      font-family: 'Inter', 'PingFang SC', 'Microsoft YaHei', system-ui, sans-serif;
      margin: 0;
      background-color: var(--bg);
      color: var(--text-main);
      line-height: 1.6;
      -webkit-font-smoothing: antialiased;
    }

    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
    }

    @media (max-width: 768px) {
      .container {
        padding: 0 16px;
      }
    }

    /* 字体层级 */
    h1, h2, h3, .font-display {
      font-family: 'Inter', 'PingFang SC', 'Microsoft YaHei', system-ui, sans-serif;
      letter-spacing: -0.02em;
    }

    .data-number {
      font-family: 'DIN Alternate', 'Inter', monospace;
      font-weight: 700;
    }

    /* 导航 */
    .navbar {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 50;
      transition: background 0.3s ease, backdrop-filter 0.3s ease;
      background: transparent;
      backdrop-filter: blur(0px);
    }

    .navbar.scrolled {
      background: var(--primary);
      backdrop-filter: blur(20px);
      box-shadow: 0 4px 20px rgba(0,0,0,0.2);
    }

    .nav-link {
      color: rgba(255,255,255,0.85);
      transition: color 0.2s;
      font-weight: 500;
    }

    .nav-link:hover {
      color: var(--accent);
    }

    .btn-primary {
      background: var(--accent);
      color: white;
      border-radius: var(--radius-btn);
      padding: 0.75rem 1.75rem;
      font-weight: 600;
      box-shadow: var(--glow);
      transition: all 0.25s ease;
      display: inline-block;
      text-align: center;
      border: none;
      cursor: pointer;
    }

    .btn-primary:hover {
      background: var(--accent-light);
      box-shadow: var(--glow-hover);
      transform: translateY(-1px);
    }

    .btn-outline-light {
      background: transparent;
      border: 1.5px solid rgba(255,255,255,0.7);
      color: white;
      border-radius: var(--radius-btn);
      padding: 0.75rem 1.75rem;
      font-weight: 600;
      transition: all 0.25s ease;
    }

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

    /* 玻璃拟态卡片 */
    .glass-card {
      background: var(--glass-bg);
      backdrop-filter: blur(12px);
      border: 1px solid var(--glass-border);
      border-radius: var(--radius-card);
      color: white;
    }

    /* 普通卡片 */
    .card {
      background: white;
      border-radius: var(--radius-card);
      box-shadow: var(--card-shadow);
      transition: transform 0.25s, box-shadow 0.25s;
    }

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

    /* 发光动画 */
    @keyframes glow-pulse {
      0% { box-shadow: 0 0 15px rgba(255,107,53,0.4); }
      50% { box-shadow: 0 0 25px rgba(255,107,53,0.7); }
      100% { box-shadow: 0 0 15px rgba(255,107,53,0.4); }
    }

    .glow-animate {
      animation: glow-pulse 2s infinite;
    }

    /* FAQ 手风琴 */
    .faq-item {
      border-bottom: 1px solid rgba(0,0,0,0.08);
      padding: 1.25rem 0;
      cursor: pointer;
    }

    .faq-question {
      font-weight: 600;
      font-size: 1.125rem;
      display: flex;
      align-items: center;
      gap: 12px;
    }

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease, padding 0.3s ease;
      background: #F0F3F8;
      border-radius: 8px;
      margin-top: 0.75rem;
      padding: 0 20px;
    }

    .faq-item.active .faq-answer {
      max-height: 200px;
      padding: 20px;
    }

    .indicator {
      width: 4px;
      height: 1.2rem;
      background: var(--accent);
      border-radius: 2px;
    }

    /* 进度条 */
    .progress-bar {
      height: 10px;
      background: rgba(255,255,255,0.2);
      border-radius: 5px;
      overflow: hidden;
    }

    .progress-fill {
      height: 100%;
      background: linear-gradient(90deg, #FF6B35, #FF8255);
      border-radius: 5px;
      width: 0%;
    }

    /* 移动端菜单 */
    .mobile-menu {
      display: none;
    }

    @media (max-width: 768px) {
      .desktop-nav {
        display: none;
      }
      .mobile-menu-btn {
        display: block;
      }
    }

    /* 服务混合布局 */
    .service-grid {
      display: grid;
      grid-template-columns: 1.5fr 1fr 1fr;
      gap: 24px;
    }

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

    @media (max-width: 640px) {
      .service-grid {
        grid-template-columns: 1fr;
      }
    }

    /* 对比滑块模拟 */
    .compare-slider {
      position: relative;
    }

    .compare-before, .compare-after {
      transition: opacity 0.3s;
    }