Coolmenu with a page centered by <div>

[omar2886]

Hello,
I want to make a visual change introducing a div from the header to the footer with a margin defined by the css like this:
<blockquote id="quote"><span class="smalltext" id="quote">quote:<hr id="quote">DIV.centerpage {
width: 970px;
position: absolute;
left: 42%;
top: 0;
margin-left: -385px;
background: #FFE7B9;
}<hr id="quote"></blockquote id="quote"></span id="quote">
But now I have a problem, I changed the fromleft of the coolmenu to stay over the categories box, but in a pc with different resolution, in get depacled.
How can I fix this problem?
NB: my page is an OsCommerce based.
Thanks