<!DOCTYPE html><html lang="en"><head><meta charset="UTF-8"><meta name="viewport" content="width=p, initial-scale=1.0"><meta http-equiv="X-UA-Compatible" content="ie=edge"><title>Document</title><style>.mask{   border: 1px solid #333;   width:100px;   height:20px;   background-color: #ffcccc;}</style></head><body>   <p><span class="te">我我哦我我</span></p>   <p><span class="te">我我哦我我</span></p>    <p><span class="te">我我哦我我</span></p>   <div class="mask">1222</div>   <button onclick="change()">changeColor</button></body><script>//定义加载办法function loadjscssfile(filename,filetype){ //判断js文件   if(filetype == "js"){      //创立script标签       var fileref = document.createElement('script');  fileref.setAttribute("type","text/javascript");  fileref.setAttribute("src",filename);   }else if(filetype == "css"){  //判断css文件 //创立link标签  var fileref = document.createElement('link');  fileref.setAttribute("rel","stylesheet");  fileref.setAttribute("type","text/css");  fileref.setAttribute("href",filename); }   if(typeof fileref != "undefined"){  document.getElementsByTagName("head")[0].appendChild(fileref);   }}function change(){   loadjscssfile("static/test.css","css");}</script></html>