/* roulang page: index */
:root {
      --primary: #0F172A;
      --accent: #2563EB;
      --teal: #0D9488;
      --bg-surface: #F8FAFC;
    }
    html {
      scroll-behavior: smooth;
      font-family: system-ui, -apple-system, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
    }
    body {
      color: #334155;
      background-color: #FFFFFF;
      overflow-x: hidden;
      line-height: 1.65;
    }
    .custom-shadow {
      box-shadow: 0 4px 20px -2px rgba(15, 23, 42, 0.05);
    }
    .hero-glow {
      background: radial-gradient(circle at 50% 30%, rgba(37, 99, 235, 0.08) 0%, rgba(255, 255, 255, 0) 70%);
    }
    .accordion-content {
      max-height: 0;
      overflow: hidden;
      transition: max-height 0.3s ease-out;
    }
    .accordion-content.active {
      max-height: 250px;
    }