/* roulang page: index */
:root {
      --primary: #1A2B49;
      --primary-dark: #0D1B2A;
      --secondary: #2C5E43;
      --accent: #D99B26;
      --bg-surface: #F9F9FB;
      --text-main: #2D3748;
      --text-muted: #718096;
      --border-color: #E2E8F0;
    }
    html {
      scroll-behavior: smooth;
    }
    body {
      font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
      color: var(--text-main);
      background-color: var(--bg-surface);
      line-height: 1.75;
    }
    .custom-shadow {
      box-shadow: 0 4px 20px -2px rgba(26, 43, 73, 0.06);
    }
    .custom-shadow-hover:hover {
      box-shadow: 0 12px 28px -4px rgba(26, 43, 73, 0.12);
      transform: translateY(-4px);
    }
    .faq-answer {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.35s ease-out;
    }
    .faq-answer.open {
      max-height: 400px;
    }
    .rotate-icon {
      transition: transform 0.3s ease;
    }
    .rotate-icon.rotated {
      transform: rotate(180deg);
    }