/* roulang page: index */
:root {
      --deep-space: #0B0E1A;
      --space-blue: #111627;
      --star-gold: #F0B90B;
      --star-gold-dark: #D4A30A;
      --nebula-purple: #7B2FBE;
      --cold-white: #E8EDF5;
      --text-body: #9CA3AF;
      --text-muted: #6B7280;
      --card-bg: rgba(255,255,255,0.04);
      --card-border: rgba(255,255,255,0.08);
      --glass-blur: blur(16px);
      --radius-card: 20px;
      --radius-btn: 9999px;
      --shadow-card: 0 8px 32px rgba(0,0,0,0.4);
      --shadow-gold: 0 12px 40px rgba(240,184,11,0.15);
      --font-sans: "PingFang SC", "Microsoft YaHei", "Hiragino Sans GB", sans-serif;
      --transition-smooth: all 0.3s ease;
    }

    * {
      box-sizing: border-box;
    }

    body {
      margin: 0;
      font-family: var(--font-sans);
      background-color: var(--deep-space);
      color: var(--text-body);
      line-height: 1.75;
      -webkit-font-smoothing: antialiased;
    }

    /* 自定义容器宽度 */
    .container-custom {
      max-width: 1280px;
      margin-left: auto;
      margin-right: auto;
      padding-left: 1.5rem;
      padding-right: 1.5rem;
    }

    /* 玻璃拟态卡片基类 */
    .glass-card {
      background: var(--card-bg);
      backdrop-filter: var(--glass-blur);
      -webkit-backdrop-filter: var(--glass-blur);
      border: 1px solid var(--card-border);
      border-radius: var(--radius-card);
      box-shadow: var(--shadow-card);
      transition: var(--transition-smooth);
    }
    .glass-card:hover {
      box-shadow: var(--shadow-gold);
      border-color: rgba(240,184,11,0.3);
      transform: translateY(-4px);
    }

    /* 按钮系统 */
    .btn-primary {
      background: linear-gradient(to right, #F0B90B, #D4A30A);
      color: #0B0E1A;
      font-weight: 700;
      padding: 0.875rem 2rem;
      border-radius: 9999px;
      box-shadow: 0 4px 15px rgba(240,184,11,0.4);
      transition: var(--transition-smooth);
      display: inline-block;
      text-align: center;
      border: none;
      cursor: pointer;
    }
    .btn-primary:hover {
      box-shadow: 0 8px 25px rgba(240,184,11,0.6);
      transform: scale(1.05);
    }

    .btn-secondary {
      border: 1px solid rgba(240,184,11,0.5);
      color: #F0B90B;
      background: transparent;
      padding: 0.875rem 2rem;
      border-radius: 9999px;
      font-weight: 600;
      transition: var(--transition-smooth);
      display: inline-block;
      text-align: center;
    }
    .btn-secondary:hover {
      background: rgba(240,184,11,0.1);
      border-color: #F0B90B;
    }

    .btn-ghost {
      color: #E8EDF5;
      border: 1px solid rgba(232,237,245,0.3);
      background: transparent;
      padding: 0.875rem 2rem;
      border-radius: 9999px;
      transition: var(--transition-smooth);
      display: inline-block;
      text-align: center;
      font-weight: 500;
    }
    .btn-ghost:hover {
      border-color: #F0B90B;
      color: #F0B90B;
    }

    /* 导航栏 */
    .navbar {
      position: sticky;
      top: 0;
      z-index: 50;
      background: rgba(11,14,26,0.7);
      backdrop-filter: blur(20px);
      -webkit-backdrop-filter: blur(20px);
      border-bottom: 1px solid rgba(255,255,255,0.04);
    }
    .nav-link {
      color: #9CA3AF;
      transition: color 0.2s;
      position: relative;
      padding-bottom: 4px;
    }
    .nav-link:hover {
      color: #F0B90B;
    }
    .nav-link::after {
      content: '';
      position: absolute;
      bottom: 0;
      left: 0;
      width: 0%;
      height: 2px;
      background: #F0B90B;
      transition: width 0.3s ease;
    }
    .nav-link:hover::after {
      width: 100%;
    }

    /* 移动端菜单隐藏技巧 */
    #menu-toggle {
      display: none;
    }
    .mobile-menu {
      display: none;
    }
    @media (max-width: 768px) {
      .desktop-nav {
        display: none;
      }
      .mobile-menu-btn {
        display: block;
      }
      #menu-toggle:checked ~ .mobile-menu {
        display: flex;
        flex-direction: column;
        position: absolute;
        top: 100%;
        left: 0;
        width: 100%;
        background: rgba(11,14,26,0.95);
        backdrop-filter: blur(25px);
        padding: 1.5rem;
        gap: 1.5rem;
        border-bottom: 1px solid rgba(255,255,255,0.1);
      }
    }

    /* 星空粒子动画 */
    .star-particle {
      position: absolute;
      background: white;
      border-radius: 50%;
      opacity: 0.7;
      animation: twinkle 3s infinite alternate;
    }
    @keyframes twinkle {
      0% { opacity: 0.3; transform: scale(0.9); }
      100% { opacity: 1; transform: scale(1.1); }
    }

    /* 光晕装饰 */
    .glow-purple {
      background: radial-gradient(circle, rgba(123,47,190,0.25) 0%, transparent 70%);
      filter: blur(80px);
      position: absolute;
      border-radius: 50%;
      z-index: 0;
    }

    /* 手风琴细节 */
    details summary {
      list-style: none;
      cursor: pointer;
      display: flex;
      align-items: center;
      justify-content: space-between;
      color: #E8EDF5;
      font-weight: 600;
    }
    details summary::-webkit-details-marker {
      display: none;
    }
    .faq-icon {
      transition: transform 0.3s ease;
      font-size: 1.2rem;
      color: #F0B90B;
    }
    details[open] .faq-icon {
      transform: rotate(45deg);
    }
    details .answer {
      background: rgba(255,255,255,0.02);
      padding: 1rem;
      border-radius: 12px;
      margin-top: 0.8rem;
    }