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<!DOCTYPE html> <html> <head> <meta charset="utf-8"> <title>素材8网教程(study.sucai8.cn)</title> <style> p:nth-child(3n+0) { background:#ff0000; } </style> </head> <body> <h1>This is a heading</h1> <p>The first paragraph.</p> <p>The second paragraph.</p> <p>The third paragraph.</p> <p>The fourth paragraph.</p> <p>The fifth paragraph.</p> <p>The sixth paragraph.</p> <p>The seventh paragraph.</p> <p>The eight paragraph.</p> <p>The ninth paragraph.</p> <p><b>注意:</b> Internet Explorer 8以及更早版本的浏览器不支持:nth-child()选择器.</p> </body> </html>
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