fmpq.com
源代码：
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<!DOCTYPE html> <html> <head> <script src="https://apps.bdimg.com/libs/jquery/2.1.4/jquery.min.js"> </script> <script> $(document).ready(function(){ $("div p:first-child").css("background-color","yellow"); }); </script> </head> <body> <p>The first paragraph in body.</p> <div style="border:1px solid;"> <p>The first paragraph in div.</p> <p>The last paragraph in div.</p> </div><br> <div style="border:1px solid;"> <p>The first paragraph in another div.</p> <p>The last paragraph in another div.</p> </div> <p>The last paragraph in body.</p> </body> </html>
运行结果