<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        html {
            color: black
        }
        
        h1 {
            color: blue
        }
        
        h2 {
            color: silver
        }
    </style>
</head>

<body>
    <h1>这是 heading 1</h1>
    <h2>这是 heading 2</h2>
    <p>这是一段普通的段落。</p>
</body>

</html>