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<title>W3Cschool教程(w3cschool.cn)</title>
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p:first-child i
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background:yellow;
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<p>I am a <i>strong</i> man. I am a <i>strong</i> man.</p>
<p>I am a <i>strong</i> man. I am a <i>strong</i> man.</p>
<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>
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