Ann_G - 5:08 pm on Nov 11, 2011 (gmt 0)

I'm sure both allowTransparency="true" (sorry I forgot to try it)
and
<style type="text/css">html,body
{
background-color: #54C6E1;
margin: 0;
padding: 0;}
</style>

would have worked but it was faster to delete the iframe and put the code directly in the document. Now it's OK.
Thanks again! It's wonderful to know one can get help when stuck. You guys are awesome.