/* roulang page: index */
/* ===== 设计变量与基础Reset ===== */
    :root {
      --bg-deep: #0A0E17;
      --neon-purple: #B847F1;
      --electric-cyan: #00E5FF;
      --text-primary: #F0F3FA;
      --text-secondary: #B0B8C5;
      --glass-border: rgba(255, 255, 255, 0.08);
      --glass-bg: rgba(255, 255, 255, 0.03);
      --blur-bg: rgba(10, 14, 23, 0.8);
      --card-radius: 24px;
      --btn-radius: 12px;
    }
    
    * {
      margin: 0;
      padding: 0;
      box-sizing: border-box;
    }
    
    html {
      scroll-behavior: smooth;
      font-size: 16px;
    }
    
    body {
      font-family: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
      background-color: var(--bg-deep);
      color: var(--text-secondary);
      line-height: 1.8;
      font-weight: 400;
      overflow-x: hidden;
      -webkit-font-smoothing: antialiased;
    }
    
    /* 自定义组件风格：紫色发光与玻璃混合 */
    .glass-card {
      background: var(--glass-bg);
      backdrop-filter: blur(20px);
      -webkit-backdrop-filter: blur(20px);
      border: 1px solid var(--glass-border);
      border-radius: var(--card-radius);
      transition: all 0.35s ease;
    }
    
    .glass-card:hover {
      border-color: rgba(184, 71, 241, 0.6);
      box-shadow: 0 20px 40px -10px rgba(0, 0, 0, 0.6), 0 0 20px rgba(184, 71, 241, 0.25);
      transform: translateY(-8px);
    }
    
    .neon-text {
      background: linear-gradient(135deg, #FFFFFF 0%, #B847F1 70%);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
      text-shadow: 0 0 10px rgba(184, 71, 241, 0.5);
    }
    
    .btn-primary {
      background: #B847F1;
      color: white;
      border-radius: var(--btn-radius);
      padding: 14px 32px;
      font-weight: 600;
      letter-spacing: 0.5px;
      box-shadow: 0 0 20px rgba(184, 71, 241, 0.4);
      transition: all 0.3s ease;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      border: none;
      cursor: pointer;
    }
    
    .btn-primary:hover {
      background: #a73edb;
      box-shadow: 0 0 35px rgba(184, 71, 241, 0.7);
      transform: scale(1.05);
    }
    
    .btn-ghost {
      background: transparent;
      border: 1.5px solid #00E5FF;
      color: #00E5FF;
      border-radius: var(--btn-radius);
      padding: 14px 32px;
      font-weight: 600;
      letter-spacing: 0.5px;
      box-shadow: 0 0 8px rgba(0, 229, 255, 0.2);
      transition: all 0.3s ease;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      backdrop-filter: blur(4px);
    }
    
    .btn-ghost:hover {
      background: #00E5FF;
      color: #0A0E17;
      box-shadow: 0 0 28px rgba(0, 229, 255, 0.7);
      transform: scale(1.05);
    }
    
    /* 导航栏底部分割线发光 */
    .nav-glow {
      border-bottom: 1px solid rgba(184, 71, 241, 0.4);
      box-shadow: 0 2px 15px rgba(184, 71, 241, 0.2);
    }
    
    .active-nav {
      color: #00E5FF !important;
      position: relative;
    }
    
    .active-nav::after {
      content: '';
      position: absolute;
      bottom: -8px;
      left: 0;
      width: 100%;
      height: 3px;
      background: #00E5FF;
      box-shadow: 0 0 15px #00E5FF;
      border-radius: 3px;
    }
    
    /* Hero网格背景 */
    .hero-grid-bg {
      background-image: 
        linear-gradient(rgba(255,255,255,0.05) 1px, transparent 1px),
        linear-gradient(90deg, rgba(255,255,255,0.05) 1px, transparent 1px);
      background-size: 60px 60px;
    }
    
    /* 移动端菜单面板 */
    #mobileMenu {
      transition: opacity 0.3s ease, visibility 0.3s;
      opacity: 0;
      visibility: hidden;
    }
    #mobileMenu.active {
      opacity: 1;
      visibility: visible;
    }
    
    /* 服务卡片中间卡悬浮上移 */
    @media (min-width: 1024px) {
      .services-grid .middle-card {
        margin-top: -28px;
        position: relative;
        z-index: 2;
      }
      .services-grid .middle-card::before {
        content: '';
        position: absolute;
        inset: -3px;
        border-radius: 28px;
        background: linear-gradient(135deg, #B847F1, #00E5FF);
        opacity: 0.3;
        filter: blur(12px);
        z-index: -1;
      }
    }
    
    /* 大数字跳动感装饰 */
    .data-number {
      font-size: 68px;
      font-weight: 800;
      line-height: 1;
      background: linear-gradient(180deg, #FFFFFF 25%, #B847F1 90%);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }
    
    /* FAQ手风琴样式 */
    .faq-item {
      border-bottom: 1px solid rgba(255,255,255,0.08);
    }
    .faq-question {
      cursor: pointer;
      transition: color 0.25s;
      font-weight: 600;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease, padding 0.4s;
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding: 16px 0 20px;
    }
    .faq-item.active .faq-question {
      color: #B847F1;
      text-shadow: 0 0 8px #B847F1;
    }