Secondary background with tabbed navigation misaligned

Looks reasonably ok in IE, but way too high in Firefox

[peterdouglas]

I'm trying to finish up a website that uses a neat tabbed navigation that I got from a well respected CSS authority on the net, but modified it to have a light gray background for the content area, and and white on the sides and the top header. It was looking great until I started messing with a CSS photo gallery (which breaks in IE, but that will be another post).

I'm back to square one, no idea how I got it to work before, but the light grey background with a 1px border at the top used to perfectly line up with the bottom of the red tabs. Now there's a small gap in IE/Win and in Firefox for Mac and PC it extends way too high up, to the top of the tabs.

I thought I had it solved when I added "margin-top: 25px;" since it looked perfect in Firefox, but horrid in IE/Win. Also, the 1px wide border for the tabs extends about 1px too far down below the tabs. The html and the css all validate...

Here's where I believe the problem lays:

#background {
background-color: #E2E2E2;
padding: 10px;
border: 1px solid #333333;
}

There's more to it than that, the problem may also be somewhere in here:

#header {
float: left;
width: 100%;
font-size: 93%;
}

#header ul {
margin: 0;
padding:0;
list-style: none;
}

#header li {
float:left;
background:url("images/left.gif") no-repeat left top;
margin:0;
padding:0 0 0 9px;
}

#header a {
float:left;
display:block;
background:url("images/right.gif") no-repeat right top;
padding:5px 15px 4px 6px;
text-decoration:none;
font-weight:bold;
color:#ccc;
}

#header a:hover {
color:#FFFFFF;
}

/* Commented Backslash Hack
hides rule from IE5-Mac \*/
#header a {float:none;}
/* End IE5-Mac hack */

#header #current {
background-image:url("images/left_on.gif");
}

#header #current a {
background-image:url("images/right_on.gif");
padding-bottom:5px;
}

[peterdouglas]

I've got the problem solved now. Needed to add one more pixel, and use clear:both. Now it's fine.

[peterdouglas]

It's ok, got it working right.