body {
      font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
      margin: 0;
      padding: 0;
      background: #3b777e;
      color: #333;
    }
    header {
      background-color: #ffffff;
      color: #000000;
      padding: 20px;
      text-align: center;
      width: 50%;
      border-radius: 8px;
      margin: auto;
    }
    h1 {
      margin: 0;
    }
    main {
      max-width: 1000px;
      margin: auto;
      padding: 20px;
    }
    section {
      margin-bottom: 40px;
      background: #fff;
      border-radius: 8px;
      box-shadow: 0 2px 4px rgba(0,0,0,0.1);
      padding: 20px;
      border: #000000 2px solid;
    }
    h2 {
      border-left: 4px solid #0366d6;
      padding-left: 10px;
      color: #0366d6;
    }
    pre {
      background: #eee;
      padding: 10px;
      border-radius: 5px;
      overflow-x: auto;
    }
    table {
      width: 100%;
      border-collapse: collapse;
      margin-top: 10px;
    }
    th, td {
      border: 1px solid #ccc;
      padding: 8px;
      text-align: left;
    }
    th {
      background: #f0f0f0;
    }
    @media (max-width: 768px) {
      body {
        font-size: 16px;
      }
      pre {
        font-size: 14px;
      }
    }