[Theme: Twenty Twelve] Keep main nav hover color when scrolling submenu

This is crazy that I have built site after site and have not dealt with this issue.

I have a main menu navigation that is orange.

When you roll over it each link turns black.

Some of the links have a black sub menu that opens underneath.

But when I scroll down the sub menu – the main menu reverts to orange BUT I want it to stay black.

Here are my existing styles:

.main-navigation ul.nav-menu, .main-navigation div.nav-menu > ul {
    background-color: #F77323 !important;
}

.main-navigation li a:hover {
   background-color: #000!important;
}

.main-navigation li ul li a {
    background: none repeat scroll 0 0 #000!important;
    color:#999!important;
}

.main-navigation li ul li a:hover {
    color:#fff!important;
}

Can anyone help me with this?

Thanks!