<!DOCTYPE html>
<html lang="zh-CN">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Hello World - Demo</title>
    <style>
        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }

        body {
            font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
            min-height: 100vh;
            display: flex;
            justify-content: center;
            align-items: center;
            background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
        }

        .container {
            text-align: center;
            padding: 2rem;
        }

        h1 {
            font-size: 4rem;
            color: #ffffff;
            text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.2);
            margin-bottom: 1rem;
            animation: fadeInUp 1s ease-out;
        }

        p {
            font-size: 1.25rem;
            color: rgba(255, 255, 255, 0.9);
            animation: fadeInUp 1s ease-out 0.3s both;
        }

        .badge {
            display: inline-block;
            margin-top: 2rem;
            padding: 0.5rem 1rem;
            background: rgba(255, 255, 255, 0.2);
            border-radius: 20px;
            color: #ffffff;
            font-size: 0.875rem;
            animation: fadeInUp 1s ease-out 0.6s both;
        }

        @keyframes fadeInUp {
            from {
                opacity: 0;
                transform: translateY(30px);
            }
            to {
                opacity: 1;
                transform: translateY(0);
            }
        }
    </style>
</head>
<body>
    <div class="container">
        <h1>Hello World</h1>
        <p>Welcome to my GitHub Pages Demo</p>
        <span class="badge">Hosted on GitHub Pages</span>
    </div>
</body>
</html>