為什么我的不能實現(xiàn)伸縮呢？（新聞菜單）
<style>
????*{margin:0;padding:0;text-decoration:none;}
????ul{list-style:none;border-bottom:2px red solid;height:50px;}
????.first{width:500px;margin:0 auto;}
????li{float:left;margin-left:2px;margin-top:30px;}
????a{background:#ccc;}
????.on,a:hover{color:white;background:red;height:50px;}
???</style>
我這個怎么不能實現(xiàn)伸縮呢？請大神們幫忙看看
2018-07-22
window.onload=function(){????var?aA=document.getElementsByTagName('a'); for(var?i=0;?i<aA.length;?i++){ aA[i].onmouseover=function(){ var?This=this; clearInterval(This.time); This.time=setInterval(function(){ This.style.width=This.offsetWidth+8+"px"; if(This.offsetWidth>=160) clearInterval(This.time); },30) } aA[i].onmouseout=function(){ clearInterval(this.time); var?This=this; this.time=setInterval(function(){ This.style.width=This.offsetWidth-8+"px"; if(This.offsetWidth<=120){ This.style.width='120px'; clearInterval(This.time); } },30) } }}伸縮效果是靠js代碼實現(xiàn)的