/* roulang page: index */
:root {
      --bg-deep: #0A0E27;
      --bg-card: #111636;
      --glass-bg: rgba(255, 255, 255, 0.03);
      --glass-border: rgba(255, 255, 255, 0.08);
      --text-primary: #FFFFFF;
      --text-secondary: rgba(255, 255, 255, 0.8);
      --text-muted: rgba(255, 255, 255, 0.5);
      --neon-cyan: #00F0FF;
      --purple-electric: #7C3AED;
      --gradient-btn: linear-gradient(135deg, #7C3AED, #00F0FF);
      --shadow-glow: 0 0 20px rgba(0, 240, 255, 0.5);
      --radius-xl: 24px;
      --radius-2xl: 32px;
      --radius-full: 9999px;
      --font-heading: 'Inter', 'SF Pro Display', -apple-system, sans-serif;
      --font-body: 'Inter', 'SF Pro Text', -apple-system, sans-serif;
      --font-mono: 'JetBrains Mono', 'Fira Code', monospace;
      --transition-smooth: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1.2);
    }

    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }

    body {
      font-family: var(--font-body);
      background-color: var(--bg-deep);
      color: var(--text-secondary);
      line-height: 1.8;
      -webkit-font-smoothing: antialiased;
      -moz-osx-font-smoothing: grayscale;
      overflow-x: hidden;
    }

    /* 容器 */
    .container-custom {
      max-width: 1280px;
      margin: 0 auto;
      padding-left: 1.5rem;
      padding-right: 1.5rem;
    }

    /* 玻璃拟态卡片 */
    .glass-card {
      background: var(--glass-bg);
      backdrop-filter: blur(20px);
      -webkit-backdrop-filter: blur(20px);
      border: 1px solid var(--glass-border);
      border-radius: var(--radius-xl);
      box-shadow: 0 8px 32px rgba(0, 0, 0, 0.4);
      transition: var(--transition-smooth);
    }

    .glass-card:hover {
      border-color: rgba(0, 240, 255, 0.3);
      box-shadow: 0 16px 48px rgba(0, 240, 255, 0.15);
      transform: translateY(-4px);
    }

    /* 发光按钮 */
    .btn-glow {
      background: var(--gradient-btn);
      border: none;
      color: white;
      font-weight: 600;
      border-radius: var(--radius-full);
      padding: 0.75rem 2rem;
      box-shadow: var(--shadow-glow);
      transition: var(--transition-smooth);
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 0.5rem;
      cursor: pointer;
    }

    .btn-glow:hover {
      box-shadow: 0 0 30px rgba(0, 240, 255, 0.8);
      transform: scale(1.05);
    }

    .btn-outline {
      border: 2px solid var(--neon-cyan);
      color: var(--neon-cyan);
      background: transparent;
      font-weight: 600;
      border-radius: var(--radius-full);
      padding: 0.75rem 2rem;
      transition: var(--transition-smooth);
      cursor: pointer;
    }

    .btn-outline:hover {
      background: rgba(0, 240, 255, 0.1);
      box-shadow: 0 0 15px rgba(0, 240, 255, 0.4);
    }

    /* 渐变文字 */
    .text-gradient {
      background: linear-gradient(135deg, #00F0FF, #7C3AED);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }

    /* 粒子背景模拟 */
    .hero-bg {
      background: radial-gradient(circle at 30% 40%, rgba(124, 58, 237, 0.15) 0%, transparent 50%),
                  radial-gradient(circle at 80% 20%, rgba(0, 240, 255, 0.1) 0%, transparent 40%),
                  var(--bg-deep);
      position: relative;
      overflow: hidden;
    }

    .hero-bg::before {
      content: "";
      position: absolute;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      background-image: url("data:image/svg+xml,%3Csvg width='60' height='60' viewBox='0 0 60 60' xmlns='http://www.w3.org/2000/svg'%3E%3Cg fill='none' fill-rule='evenodd'%3E%3Cg fill='%23ffffff' fill-opacity='0.03'%3E%3Cpath d='M36 34v-4h-2v4h-4v2h4v4h2v-4h4v-2h-4zm0-30V0h-2v4h-4v2h4v4h2V6h4V4h-4zM6 34v-4H4v4H0v2h4v4h2v-4h4v-2H6zM6 4V0H4v4H0v2h4v4h2V6h4V4H6z'/%3E%3C/g%3E%3C/g%3E%3C/svg%3E");
      pointer-events: none;
    }

    /* 导航栏 */
    .navbar {
      background: rgba(10, 14, 39, 0.7);
      backdrop-filter: blur(24px);
      -webkit-backdrop-filter: blur(24px);
      border-bottom: 1px solid rgba(255, 255, 255, 0.05);
      position: sticky;
      top: 0;
      z-index: 50;
    }

    .nav-link {
      color: rgba(255, 255, 255, 0.7);
      font-weight: 500;
      transition: color 0.2s;
      position: relative;
    }

    .nav-link:hover {
      color: white;
    }

    .nav-link::after {
      content: '';
      position: absolute;
      bottom: -4px;
      left: 0;
      width: 100%;
      height: 2px;
      background: var(--neon-cyan);
      transform: scaleX(0);
      transition: transform 0.25s;
    }

    .nav-link:hover::after {
      transform: scaleX(1);
    }

    /* 数据看板模拟 */
    .data-card {
      background: rgba(17, 22, 54, 0.7);
      backdrop-filter: blur(16px);
      border: 1px solid rgba(255, 255, 255, 0.1);
      border-radius: 20px;
      padding: 1.25rem;
      box-shadow: 0 8px 24px rgba(0,0,0,0.5);
    }

    .data-number {
      font-family: var(--font-mono);
      color: var(--neon-cyan);
      font-weight: 600;
    }

    /* FAQ 手风琴 */
    .faq-item {
      border-bottom: 1px solid rgba(255,255,255,0.08);
    }

    .faq-question {
      cursor: pointer;
      display: flex;
      align-items: center;
      justify-content: space-between;
      padding: 1.5rem 0;
      font-weight: 600;
      color: white;
    }

    .faq-icon {
      width: 24px;
      height: 24px;
      border: 2px solid var(--neon-cyan);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      color: var(--neon-cyan);
      transition: transform 0.3s;
      flex-shrink: 0;
      margin-left: 1rem;
    }

    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease, padding 0.4s;
      color: rgba(255,255,255,0.7);
    }

    .faq-item.active .faq-answer {
      max-height: 200px;
      padding-bottom: 1.5rem;
    }

    .faq-item.active .faq-icon {
      transform: rotate(45deg);
      background: rgba(0,240,255,0.15);
    }

    /* 输入框 */
    .input-glass {
      background: rgba(255,255,255,0.05);
      border: 1px solid rgba(255,255,255,0.1);
      border-radius: 16px;
      padding: 0.9rem 1.25rem;
      color: white;
      transition: border 0.2s, box-shadow 0.2s;
      width: 100%;
      outline: none;
    }

    .input-glass:focus {
      border-color: var(--neon-cyan);
      box-shadow: 0 0 12px rgba(0,240,255,0.3);
    }

    /* 页脚链接 */
    .footer-link {
      color: rgba(255,255,255,0.6);
      transition: color 0.2s;
    }

    .footer-link:hover {
      color: var(--neon-cyan);
    }

    @media (max-width: 768px) {
      .hero-split {
        flex-direction: column;
      }
      .mobile-menu {
        display: block;
      }
      .desktop-menu {
        display: none;
      }
    }