W3School TIY
编辑您的代码：
<html> <head> <style type="text/css"> p.topmargin { margin-top: 25% } </style> </head> <body> <p>This is a paragraph with no margin specified</p> <p class="topmargin">This is a paragraph with a specified top margin</p> </body> </html>
查看结果: