/* roulang page: index */
:root {
      --deep-blue: #0A0E27;
      --body-bg: #060918;
      --cyan: #00E5FF;
      --purple: #7B2FBE;
      --glass-bg: rgba(255, 255, 255, 0.03);
      --glass-border: rgba(0, 229, 255, 0.15);
      --text-primary: #E0E8F0;
      --text-secondary: #B0C4DE;
      --text-muted: #6A7A94;
      --card-radius: 24px;
      --btn-radius: 50px;
      --shadow-glow: 0 20px 40px rgba(0,0,0,0.6);
      --cyan-glow: 0 0 30px rgba(0,229,255,0.6);
    }
    * {
      box-sizing: border-box;
      margin: 0;
      padding: 0;
    }
    html {
      scroll-behavior: smooth;
    }
    body {
      background-color: var(--body-bg);
      font-family: 'Inter', 'PingFang SC', 'Microsoft YaHei', sans-serif;
      color: var(--text-primary);
      line-height: 1.6;
      -webkit-font-smoothing: antialiased;
      overflow-x: hidden;
    }
    .container {
      max-width: 1280px;
      margin: 0 auto;
      padding: 0 24px;
    }
    @media (max-width: 768px) {
      .container {
        padding: 0 20px;
      }
    }
    /* 自定义玻璃拟态卡片 */
    .glass-card {
      background: rgba(10, 14, 39, 0.35);
      backdrop-filter: blur(20px);
      -webkit-backdrop-filter: blur(20px);
      border: 1px solid var(--glass-border);
      border-radius: var(--card-radius);
      box-shadow: var(--shadow-glow), inset 0 0 0 1px rgba(255,255,255,0.05);
      transition: all 0.3s ease;
    }
    .glass-card:hover {
      border-color: rgba(0,229,255,0.35);
      box-shadow: 0 25px 45px rgba(0,0,0,0.7), 0 0 20px rgba(0,229,255,0.2);
    }
    .glass-card-sm {
      background: rgba(10, 14, 39, 0.3);
      backdrop-filter: blur(18px);
      -webkit-backdrop-filter: blur(18px);
      border: 1px solid rgba(0,229,255,0.12);
      border-radius: 16px;
      transition: transform 0.2s, border-color 0.3s;
    }
    .glass-card-sm:hover {
      border-color: rgba(0,229,255,0.3);
      transform: translateY(-4px);
    }
    /* 发光按钮 */
    .btn-glow {
      background: linear-gradient(135deg, var(--cyan), var(--purple));
      border: none;
      border-radius: var(--btn-radius);
      padding: 14px 32px;
      font-weight: 600;
      color: #fff;
      font-size: 1rem;
      letter-spacing: 0.5px;
      box-shadow: 0 8px 20px rgba(0,229,255,0.3);
      transition: all 0.3s ease;
      cursor: pointer;
      display: inline-flex;
      align-items: center;
      justify-content: center;
      text-decoration: none;
      backdrop-filter: blur(10px);
    }
    .btn-glow:hover {
      box-shadow: var(--cyan-glow), 0 10px 25px rgba(123,47,190,0.4);
      transform: translateY(-2px);
    }
    .btn-outline {
      background: transparent;
      border: 1.5px solid var(--cyan);
      color: var(--cyan);
      border-radius: var(--btn-radius);
      padding: 14px 32px;
      font-weight: 600;
      backdrop-filter: blur(10px);
      transition: all 0.3s;
      cursor: pointer;
      text-decoration: none;
      display: inline-flex;
      align-items: center;
    }
    .btn-outline:hover {
      background: rgba(0,229,255,0.1);
      border-color: #fff;
      color: #fff;
      box-shadow: 0 0 18px rgba(0,229,255,0.5);
    }
    /* 文本层级 */
    h1, h2, h3 {
      font-weight: 700;
      letter-spacing: -0.02em;
    }
    .text-glow {
      color: var(--cyan);
      text-shadow: 0 0 8px rgba(0,229,255,0.5);
    }
    /* 导航毛玻璃 */
    .nav-glass {
      background: rgba(6, 9, 24, 0.7);
      backdrop-filter: blur(20px);
      -webkit-backdrop-filter: blur(20px);
      border-bottom: 1px solid rgba(0,229,255,0.15);
    }
    .nav-link {
      position: relative;
      padding: 8px 0;
      color: var(--text-secondary);
      font-weight: 500;
      transition: color 0.3s;
      text-decoration: none;
    }
    .nav-link::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0;
      height: 2px;
      background: var(--cyan);
      box-shadow: 0 0 12px var(--cyan);
      transition: width 0.3s;
    }
    .nav-link:hover {
      color: #fff;
    }
    .nav-link:hover::after {
      width: 100%;
    }
    /* 移动端底部导航 */
    .mobile-nav {
      background: rgba(10, 14, 39, 0.85);
      backdrop-filter: blur(25px);
      border-top: 1px solid rgba(0,229,255,0.2);
    }
    @media (max-width: 768px) {
      .desktop-nav { display: none; }
      .mobile-nav { display: flex; }
    }
    @media (min-width: 769px) {
      .mobile-nav { display: none; }
      .desktop-nav { display: flex; }
    }
    /* FAQ手风琴 */
    .faq-item {
      border-bottom: 1px solid rgba(0,229,255,0.12);
    }
    .faq-question {
      cursor: pointer;
      padding: 1.2rem 0;
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-weight: 600;
      color: #fff;
    }
    .faq-icon {
      transition: transform 0.3s;
      color: var(--cyan);
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.4s ease;
      color: var(--text-secondary);
    }
    .faq-item.active .faq-icon {
      transform: rotate(45deg);
    }
    .faq-item.active .faq-answer {
      max-height: 200px;
      padding-bottom: 1rem;
    }
    /* 数据跳动 */
    @keyframes pulse {
      0% { opacity: 0.7; transform: scale(1); }
      50% { opacity: 1; transform: scale(1.02); }
      100% { opacity: 0.7; transform: scale(1); }
    }
    .animate-pulse-slow {
      animation: pulse 2.5s infinite;
    }