<!doctype html>
<html>

Will be green if relative positioning offsets are supported:

<table border=0 cellpadding=0 cellspacing=0>
<tr><td style="width:100px;height:100px;background-color:red">
<tr><td style="position:relative; width:100px;height:100px; top:-100px;background-color:green">
</table>