<box xmlns="http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul">
<stack>
<label top="20px" left="20px" style="color:black; text-shadow: purple 4px 4px, red 7px 7px, green 10px 10px, grey 13px 13px;" value="Hello"/>
</stack>
</box>