/* roulang page: index */
:root {
      --primary: #4F46E5;
      --accent: #06B6D4;
      --success: #10B981;
      --text-main: #0F172A;
      --bg-surface: #F8FAFC;
      --card-bg: #FFFFFF;
      --dark-obsidian: #090D16;
    }
    * {
      box-sizing: border-box;
    }
    body {
      font-family: system-ui, -apple-system, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
      letter-spacing: 0.01em;
      color: var(--text-main);
      background-color: var(--bg-surface);
      overflow-x: hidden;
      margin: 0;
      padding: 0;
    }
    html {
      scroll-behavior: smooth;
    }
    .accordion-content {
      transition: max-height 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    }