/* roulang page: index */
/* :root 设计变量 & 全局重置 */
    :root {
      --primary: #E43D0E;
      --primary-hover: #C9330B;
      --accent: #F5A623;
      --bg-dark: #0B0E14;
      --bg-card: #161A22;
      --text-main: #F2F2F2;
      --text-secondary: #9CA3AF;
      --border-light: rgba(255,255,255,0.08);
      --border-hover: rgba(255,255,255,0.2);
      --radius-lg: 1rem;
      --radius-md: 0.75rem;
      --shadow-card: 0 4px 12px rgba(0,0,0,0.5);
      --transition-fast: 0.2s ease;
    }
    
    * {
      box-sizing: border-box;
    }
    
    body {
      margin: 0;
      font-family: "PingFang SC", "Microsoft YaHei", "Helvetica Neue", sans-serif;
      background-color: var(--bg-dark);
      color: var(--text-main);
      line-height: 1.6;
      -webkit-font-smoothing: antialiased;
    }
    
    /* 自定义滚动条 */
    ::-webkit-scrollbar {
      width: 6px;
    }
    ::-webkit-scrollbar-track {
      background: var(--bg-dark);
    }
    ::-webkit-scrollbar-thumb {
      background: var(--primary);
      border-radius: 3px;
    }
    
    /* 容器统一 */
    .container-custom {
      max-width: 1280px;
      margin-left: auto;
      margin-right: auto;
      padding-left: 1.5rem;
      padding-right: 1.5rem;
    }
    @media (min-width: 1024px) {
      .container-custom {
        padding-left: 2rem;
        padding-right: 2rem;
      }
    }
    
    /* 导航模糊背景 */
    .nav-blur {
      background: rgba(11, 14, 24, 0.88);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
      border-bottom: 1px solid var(--border-light);
    }
    
    /* 移动端汉堡菜单动画 */
    .mobile-menu {
      transition: transform 0.25s ease, opacity 0.25s ease;
      transform: translateY(-10px);
      opacity: 0;
      pointer-events: none;
    }
    .mobile-menu.open {
      transform: translateY(0);
      opacity: 1;
      pointer-events: auto;
    }
    
    /* Hero 光晕效果 */
    .hero-glow {
      position: relative;
    }
    .hero-glow::before {
      content: "";
      position: absolute;
      top: -20%;
      left: -10%;
      width: 60%;
      height: 80%;
      background: radial-gradient(circle at 30% 30%, rgba(228, 61, 14, 0.25), transparent 70%);
      pointer-events: none;
      z-index: 0;
    }
    
    /* 卡片hover */
    .card-hover {
      transition: transform 0.3s ease, border-color 0.2s ease, background-color 0.2s ease;
      background-color: rgba(22, 26, 34, 0.9);
      border: 1px solid var(--border-light);
      border-radius: var(--radius-lg);
    }
    .card-hover:hover {
      transform: translateY(-6px);
      border-color: var(--border-hover);
      background-color: rgba(30, 36, 46, 0.95);
    }
    
    /* 按钮系统 */
    .btn-primary {
      background-color: var(--primary);
      color: white;
      font-weight: 700;
      padding: 0.9rem 2.2rem;
      border-radius: 0.75rem;
      transition: background-color 0.2s, transform 0.15s;
      display: inline-block;
      text-align: center;
      border: none;
      cursor: pointer;
      font-size: 1rem;
    }
    .btn-primary:hover {
      background-color: var(--primary-hover);
      transform: scale(1.02);
    }
    
    .btn-secondary {
      border: 2px solid var(--primary);
      color: var(--primary);
      background: transparent;
      font-weight: 700;
      padding: 0.9rem 2.2rem;
      border-radius: 0.75rem;
      transition: all 0.2s;
      display: inline-block;
      text-align: center;
      cursor: pointer;
    }
    .btn-secondary:hover {
      background-color: var(--primary);
      color: white;
      transform: scale(1.02);
    }
    
    /* FAQ手风琴 */
    .faq-item {
      border-bottom: 1px solid var(--border-light);
    }
    .faq-question {
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
      padding: 1.2rem 0;
      font-weight: 600;
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease, padding 0.2s;
      color: var(--text-secondary);
    }
    .faq-item.active .faq-answer {
      max-height: 15rem;
      padding-bottom: 1.2rem;
    }
    .faq-icon {
      color: var(--primary);
      font-size: 1.5rem;
      transition: transform 0.3s;
    }
    .faq-item.active .faq-icon {
      transform: rotate(45deg);
    }
    
    /* 数字统计跳动感 */
    @keyframes countPulse {
      0% { transform: scale(1); }
      50% { transform: scale(1.05); color: #F5A623; }
      100% { transform: scale(1); }
    }
    .stat-number {
      display: inline-block;
      animation: countPulse 2s infinite;
    }
    
    /* 装饰线条 */
    .decor-line {
      width: 4px;
      height: 2.5rem;
      background-color: var(--primary);
      display: inline-block;
      margin-right: 0.75rem;
      border-radius: 2px;
    }