xxxxxxxxxx<html><head><meta charset="utf-8"> <title>W3Cschool教程(w3cschool.cn)</title><style> h1 {font-size:250%;} h2 {font-size:200%;} p {font-size:100%;}</style></head><body> <h1>这是标题 1</h1> <h2>这是标题 2</h2> <p>这是段落。</p></body></html>