/* roulang page: index */
:root {
      --primary: #2563EB;
      --primary-dark: #1D4ED8;
      --primary-light: #EFF6FF;
      --accent: #F97316;
      --accent-dark: #EA580C;
      --success: #10B981;
      --text-main: #0F172A;
      --text-soft: #475569;
      --text-weak: #94A3B8;
      --bg-white: #FFFFFF;
      --bg-light: #F8FAFC;
      --border-light: #E2E8F0;
    }
    *, *::before, *::after { box-sizing: border-box; }
    body {
      margin: 0;
      font-family: 'Inter', 'PingFang SC', 'Microsoft YaHei', 'Noto Sans SC', sans-serif;
      color: #0F172A;
      background-color: #FFFFFF;
      line-height: 1.6;
      -webkit-font-smoothing: antialiased;
    }
    img { max-width: 100%; height: auto; display: block; }
    a { color: inherit; text-decoration: none; }
    button, input, textarea { font-family: inherit; }
    .container-main {
      max-width: 1280px;
      margin-left: auto;
      margin-right: auto;
      padding-left: 1.5rem;
      padding-right: 1.5rem;
    }
    @media (min-width: 1024px) {
      .container-main { padding-left: 2rem; padding-right: 2rem; }
    }
    .nav-blur {
      background: rgba(255,255,255,0.85);
      backdrop-filter: blur(12px);
      -webkit-backdrop-filter: blur(12px);
    }
    .shadow-card {
      box-shadow: 0 4px 12px rgba(0,0,0,0.04), 0 1px 2px rgba(0,0,0,0.02);
    }
    .hover-lift {
      transition: all 0.3s ease;
    }
    .hover-lift:hover {
      transform: translateY(-4px);
      box-shadow: 0 20px 30px -12px rgba(37,99,235,0.15), 0 8px 14px -6px rgba(0,0,0,0.05);
      border-color: rgba(37,99,235,0.25);
    }
    .accent-badge {
      background-color: #F97316;
      color: white;
      font-size: 0.75rem;
      font-weight: 600;
      padding: 0.25rem 0.75rem;
      border-radius: 2rem;
      letter-spacing: 0.02em;
    }
    .faq-details summary {
      list-style: none;
      cursor: pointer;
      display: flex;
      justify-content: space-between;
      align-items: center;
      font-weight: 600;
      color: #0F172A;
      padding: 1.25rem 0;
      border-bottom: 1px solid #E2E8F0;
      transition: color 0.2s;
    }
    .faq-details summary:hover { color: #2563EB; }
    .faq-details summary::-webkit-details-marker { display: none; }
    .faq-details[open] summary { color: #2563EB; border-bottom-color: #2563EB; }
    .faq-details .faq-content {
      padding: 1rem 0 1.5rem;
      color: #475569;
      line-height: 1.7;
    }
    .mobile-menu {
      display: none;
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100vh;
      background: rgba(255,255,255,0.98);
      backdrop-filter: blur(20px);
      flex-direction: column;
      align-items: center;
      justify-content: center;
      gap: 2rem;
      z-index: 60;
      transform: translateY(-100%);
      transition: transform 0.35s ease;
    }
    .mobile-menu.open {
      display: flex;
      transform: translateY(0);
    }
    @media (min-width: 1024px) {
      .mobile-menu { display: none !important; }
    }