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User input: 给这个html文件增加一些css样式使其好简易的网站的样子
Patch:
text
*** Begin Patch
*** Update File: testDemo/hello.html
<!DOCTYPE html>
<html>
<head>
    <title>Hello</title>
    <style>
        body {
            font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
            background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
            margin: 0;
            padding: 0;
            display: flex;
            justify-content: center;
            align-items: center;
            min-height: 100vh;
            color: #333;
        }
        .container {
            background-color: white;
            border-radius: 20px;
            box-shadow: 0 15px 35px rgba(0, 0, 0, 0.1);
            padding: 40px 50px;
            text-align: center;
            max-width: 600px;
            width: 90%;
            border: 1px solid #e0e0e0;
        }
        h1 {
            font-size: 3.5rem;
            margin-bottom: 20px;
            color: #2c3e50;
            letter-spacing: 1px;
        }
        p {
            font-size: 1.4rem;
            line-height: 1.6;
            color: #555;
            margin-bottom: 30px;
        }
        .highlight {
            color: #3498db;
            font-weight: bold;
        }
        .footer {
            margin-top: 40px;
            font-size: 0.9rem;
            color: #7f8c8d;
            border-top: 1px dashed #ddd;
            padding-top: 20px;
        }
    </style>
</head>
<body>
    <div class="container">
        <h1>Hello, World!</h1>
        <p>This is a simple website created with HTML and CSS.</p>
        <p>You can easily customize this page by editing the <span class="highlight">style</span> tag in the head section.</p>
        <div class="footer">
            <p>Built with ❤️ using Code Agent</p>
        </div>
    </div>
</body>
</html>
*** End Patch