请教各位一个问题，求解答：请大佬帮忙看下一句代码的意思，花费您2两分钟，小弟想了好久了十分感谢

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题目描述做一个改变div宽高背景色重置的项目题目来源及自己的思路在网上找了个高级的实现思路相关代码控制div属性#outer{width:500px;margin:0auto;padding:0;text-align:center;}#div1{width:100px;height:100px;background:black;margin:10pxauto;display:block;}varchangeStyle=function(elem,attr,value){elem.style[attr]=value};window.onload=function(){varoBtn=document.getElementsByTagName("input");varoDiv=document.getElementById("div1");varoAtt=["width","height","background","display","display"];varoVal=["200px","200px","red","none","block"];for(vari=0;i