/* roulang page: index */
/* 设计变量与全局重置 */
    :root {
      --primary: #0A0F1D;
      --accent: #E6003A;
      --bg-white: #FFFFFF;
      --bg-light: #F5F6FA;
      --text-main: #1A1A1A;
      --text-muted: #6B7280;
      --border-light: #E5E7EB;
      --success: #10B981;
      --shadow-card: 0 20px 40px -15px rgba(10,15,29,0.08);
      --font-heading: 'Inter', system-ui, -apple-system, 'Microsoft YaHei', 'PingFang SC', sans-serif;
      --font-body: 'Inter', system-ui, -apple-system, 'Microsoft YaHei', 'PingFang SC', sans-serif;
      --font-number: 'DIN Alternate', 'Inter', system-ui, sans-serif;
    }
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    body {
      font-family: var(--font-body);
      color: var(--text-main);
      background-color: var(--bg-white);
      line-height: 1.6;
      -webkit-font-smoothing: antialiased;
      overflow-x: hidden;
    }
    h1, h2, h3, h4 {
      font-family: var(--font-heading);
      letter-spacing: -0.02em;
      font-weight: 700;
    }
    .container {
      max-width: 1280px;
      margin-left: auto;
      margin-right: auto;
      padding-left: 24px;
      padding-right: 24px;
    }
    @media (max-width: 768px) {
      .container {
        padding-left: 16px;
        padding-right: 16px;
      }
    }
    /* 导航样式 */
    .navbar {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      z-index: 50;
      transition: background 0.25s ease, box-shadow 0.25s ease, backdrop-filter 0.25s ease;
      background: transparent;
    }
    .navbar.scrolled {
      background: rgba(255,255,255,0.94);
      backdrop-filter: blur(12px);
      box-shadow: 0 4px 20px rgba(0,0,0,0.03);
      border-bottom: 1px solid rgba(229,231,235,0.6);
    }
    .nav-link {
      color: white;
      transition: color 0.2s;
      font-weight: 500;
    }
    .navbar.scrolled .nav-link {
      color: var(--primary);
    }
    .nav-link:hover {
      color: var(--accent);
    }
    .logo-text {
      font-weight: 800;
      font-size: 1.5rem;
      letter-spacing: -0.02em;
      color: white;
    }
    .navbar.scrolled .logo-text {
      color: var(--primary);
    }
    .btn-primary {
      background: var(--accent);
      color: white;
      border-radius: 0px;
      padding: 0.7rem 1.8rem;
      font-weight: 600;
      transition: background 0.2s, transform 0.1s;
      border: none;
      cursor: pointer;
      text-decoration: none;
      display: inline-block;
    }
    .btn-primary:hover {
      background: #C4002F;
    }
    .btn-outline {
      background: transparent;
      border: 1px solid var(--primary);
      color: var(--primary);
      border-radius: 0px;
      padding: 0.7rem 1.8rem;
      font-weight: 600;
      transition: all 0.2s;
      text-decoration: none;
    }
    .btn-outline:hover {
      background: var(--primary);
      color: white;
    }
    /* 汉堡菜单 */
    .mobile-menu {
      display: none;
    }
    @media (max-width: 768px) {
      .desktop-nav-links {
        display: none;
      }
      .mobile-menu {
        display: block;
      }
    }
    /* Hero 直播波纹模拟 */
    .live-pulse {
      display: inline-block;
      width: 10px;
      height: 10px;
      background: var(--success);
      border-radius: 50%;
      box-shadow: 0 0 0 0 rgba(16,185,129,0.5);
      animation: pulse-ring 1.8s infinite;
      margin-right: 6px;
    }
    @keyframes pulse-ring {
      0% { box-shadow: 0 0 0 0 rgba(16,185,129,0.6); }
      70% { box-shadow: 0 0 0 8px rgba(16,185,129,0); }
      100% { box-shadow: 0 0 0 0 rgba(16,185,129,0); }
    }
    /* 数据滚动数字样式 */
    .stat-number {
      font-family: var(--font-number);
      font-weight: 700;
      font-size: 3rem;
      line-height: 1.2;
    }
    /* FAQ 手风琴 */
    .faq-item {
      border-bottom: 1px solid var(--border-light);
    }
    .faq-question {
      cursor: pointer;
      font-weight: 600;
      padding: 1.2rem 0;
      display: flex;
      justify-content: space-between;
      align-items: center;
      color: var(--primary);
      transition: color 0.2s;
    }
    .faq-question:hover {
      color: var(--accent);
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease, padding 0.3s ease;
      color: var(--text-muted);
      background: #f9fafb;
      padding: 0 1rem;
      margin-bottom: 0;
    }
    .faq-item.active .faq-answer {
      max-height: 220px;
      padding: 1rem;
      margin-bottom: 0.5rem;
    }
    .faq-icon {
      font-size: 1.4rem;
      font-weight: 400;
      transition: transform 0.2s;
    }
    .faq-item.active .faq-icon {
      transform: rotate(45deg);
    }
    /* 卡片动效 */
    .card-solution {
      transition: all 0.3s ease;
      border-left: 3px solid var(--accent);
      padding-left: 1.6rem;
    }
    .card-solution:hover {
      background: #fafbfc;
    }
    /* 底部 */
    .footer-link {
      color: #9CA3AF;
      transition: color 0.2s;
      text-decoration: none;
    }
    .footer-link:hover {
      color: white;
    }
    /* 自定义滚动条 */
    ::-webkit-scrollbar{width:6px}
    ::-webkit-scrollbar-track{background:#f1f1f1}
    ::-webkit-scrollbar-thumb{background:#c1c1c1; border-radius:3px}