Background Color wont Display in FF

[admin]

Hi guys for some reason the background color for a div wont display in FF where it does in IE not sure why? This CSS stuff is very frustrating.

url: <!-- m --><a class="postlink" href="http://www.rocketss.com/franks/sitemap/">http://www.rocketss.com/franks/sitemap/</a><!-- m -->

CSS: for that section is:

#toplevelnav {
float:left;
left:0em;
top:0em;
width:100%;
margin: 0em 0em 0em 0em;
padding: 0em 0em 0 0em;

}

#toplevelnav .leftside {
float:left;
background-color: #003882;
width:30%;
margin: 0 0em 0 0;

}

#toplevelnav .rightside {
float:right;
background-color: #003882;
width:69%;
margin: 0 0em 0 0em;

}put some content in and it will


<span class="leftside"> </span>
<span class="rightside"> </span>