body {
            font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
            margin: 0;
            padding: 0;
            background-color: #f5f5f7;
            color: #333;
            line-height: 1.6;
        }
        header {
            background-color: #24292e;
            color: #ffffff;
            padding: 20px;
            text-align: center;
            position: relative;
        }
        header h1 {
            margin: 0;
            font-size: 2.5em;
        }
        header p {
            margin: 0;
            font-size: 1.2em;
        }
        section {
            max-width: 800px;
            margin: 20px auto;
            padding: 20px;
            background-color: #ffffff;
            border-radius: 8px;
            box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
        }
        section h2 {
            font-size: 2em;
            border-bottom: 2px solid #e5e5e5;
            padding-bottom: 10px;
            margin-bottom: 20px;
            color: #0366d6;
        }
        ul {
            list-style-type: none;
            padding: 0;
        }
        ul li {
            margin-bottom: 15px;
        }
        .contact-info {
            text-align: center;
        }
        .contact-info a {
            color: #0366d6;
            text-decoration: none;
        }
        .contact-info a:hover {
            text-decoration: underline;
        }
        .language-toggle {
            position: absolute;
            top: 20px;
            right: 20px;
        }
        .language-toggle button {
            background-color: #0366d6;
            color: #ffffff;
            border: none;
            padding: 10px;
            border-radius: 5px;
            cursor: pointer;
        }
        .language-toggle button:hover {
            background-color: #005bb5;
        }
        .cn {
            display: none;
        }