W3School TIY
编辑您的代码：
<html> <head> <script type="text/javascript" src="../jquery/jquery.js"></script> </head> <body> <p>one</p> <div><p>two</p></div> <p>three</p> <script>$("div > p").css("border", "1px solid gray");</script> </body> </html>
查看结果: