Multiple browsers compatible with pure DIV/CSS couplet floating ad code without js_Experience exchange

. r1{width:80px;height:80px;background:red;float:right;
position:fixed !important; top/**/:200px;
position:absolute; z-index:300; top: expression(offsetParent.scrollTop 200);right:20px;}
.r2{width:80px;height:80px;background:red;float:right;
position:fixed !important; top/**/: 300px;
position:absolute; z-index:400; top:expression(offsetParent.scrollTop 300);right:20px;}
.l1{width:80px;height:80px;background:red;float: right;
position:fixed !important; top/**/:200px;
position:absolute; z-index:300; top:expression(offsetParent.scrollTop 200);left:20px;}
.l2{width:80px;height:80px;background:red;float:right;
position:fixed !important; top/**/:300px;
position:absolute; z-index:400; top :expression(offsetParent.scrollTop 300);left:20px;}

 
 
 
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