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<!DOCTYPE html> <meta charset="utf-8"><link href="/static/next/css/tryit.css?v=2017082407" rel="stylesheet"/> <style> p:first-child { background-color:yellow; } </style> <p>This paragraph is the first child of its parent (body).</p> <h1>Welcome to My Homepage</h1> <p>This paragraph is not the first child of its parent.</p> <div> <p>This paragraph is the first child of its parent (div).</p> <p>This paragraph is not the first child of its parent.</p> </div> <p><b>注意:</b> :first-child作用于 IE8以及更早版本的浏览器, DOCTYPE必须已经声明.</p> <footer>简单教程，简单编程<br/>Copyright © 简单教程 www.twle.cn</footer>
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