为什么我都去掉所有js引用，点击返回顶部他还是能返回到顶部。。。难道我疯了？
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8"/>
<title>Document</title>
</head>
<body>
这里忽略<p>1111</p>*100个，我写了
<div >
<a href="" >
<span >afaf
</span>
</a>
<a href="" >
<span >1avv
</span>
</a>
<a href="" >
<span >vxv
</span>111
</a>
<a id="backTop" href="" >
<span >avav
</span>
</a>
</div>
</body>
</html>
