<!DOCTYPE html>
<html>
<head>
<title></title>
<script type="text/javascript" src="jquery.min.js"></script>
<style type="text/css">
a{
float:left;
display: block;
margin:50px;
width:100px;
line-height:100px;
text-align:center;
height:100px;
color:#fff;
border-radius:50px;
text-decoration: none;
}
</style>
<script type="text/javascript">
function aa(tag){
var len=document.getElementsByTagName(tag).length
for(var i=0;i<len;i++){
document.getElementsByTagName(tag)[i].style.backgroundColor='rgb('+Math.floor(Math.random()*256)+','+Math.floor(Math.random()*256)+','+Math.floor(Math.random()*256)+')'
}
}
$(document).ready(function(){
aa('a')
$('a').mouseover(function(){
$bg=$(this).css('backgroundColor')
$(this).css('box-shadow','0px 0px 20px '+$bg)
$(this).css('border-radius','20px ')
})
$('a').mouseleave(function(){
$bg=$(this).css('backgroundColor')
$(this).css('box-shadow','none')
$(this).css('border-radius','50px ')
})
})
</script>
</head>
<body>
<a href="#">1</a>
<a href="#">2</a>
<a href="#">3</a>
<a href="#">4</a>
</body>
</html>
$(this)代表获取当前所有属性吗?