CSS Menu - Keep main menu item highlighted

[bubbagump]

Hey hey....

Need some help with CSS menus. I need to figure out how to keep my main
menu items highlighted when I am hovering on sub-items or
sub-sub-items. Here is my code:

#menu {
width: 161px;
}

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

#menu a, #menu h2 {
font: bold 11px/16px arial, helvetica, sans-serif;
display: block;
margin: 0;
padding: 2px 3px;
text-transform: uppercase;
}

#menu h2 {
color: #fff;
background: #000;
text-transform: uppercase;
}

#menu a {
color: #fff;
text-decoration: none;
}

#menu a:hover {
color: #000;
border-width: 1px;
border-style: solid;
border-color: #ccc #888 #555 #bbb;
margin: 0;
padding: 1px 3px;
}

#menu li {position: relative;}

#menu ul ul ul a {
border-width: 1px;
border-style: solid;
border-color: #ccc #888 #555 #bbb;
padding: 1px 3px;
}

#menu ul ul ul {
position: absolute;
top: 0;
left: 100%;
width: 100%;
background: #999;
}

#menu ul ul ul UL {
position: absolute;
top: 0;
left: 100%;
width: 100%;
background: #CCC;
}

div#menu ul ul ul,
div#menu ul ul li:hover ul ul
{display: none;}

div#menu ul ul li:hover ul,
div#menu ul ul ul li:hover ul
{display: block;}

What can I do to fix this so I know what main menu option I'm under
when hovering on sub-items?

Thanks!