Change color submenu

Hello: I need to change the colors of a submenu. In the picture you can see that the main menu buttons at rest have a white background and dark text. Hovering above the background is turquoise and the text is white. That's how I need to occur in the submenu, which has very different colors, as you can see in the picture. http://i1254.photobucket.com/albums/hh605/mithrand/submenu.jpg Can you help me? Thank you very much.