rainbow border rectangle

<div style="width:420px;height:336px;background-color:#FFFFFF;border:0px;margin:auto;">
<div style="width:420px;height:320px;background-color:#FFFFFF;border:0px;margin:0px;">
<div style="float:left;width:420px;height:320px;margin:0px;"><img alt="rainbow" src="https://image.ibb.co/g42wZn/rainbow.jpg" style="width:420px;height:320px;" /></div>
<div style="float:left;width:400px;height:300px;margin:10px;background-color:#FFFFFF;margin-top:-310px;"><img alt="content" src="" style="width:400px;height:300px;border:0px;margin:0px;" /></div>
</div>
<p style="text-align:center;color:#000000;font-size:10px;font-family:calibri;margin-top:0px;margin-bottom:0px;">cr: <a href="http://www.roleplayrepublic.com/profile/view/44477">Midorin</a></p>
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