Can I use two custom classes for one menu item?

Hi, I have a couple of questions:

(1) Can I use two or more custom classes for each menu item? I ask because I already have a custom class for the top menu. It's 'mega.menu' and is part of the theme (if one wants to do this).

(2) If so, could you please give me the code to change menu item color; i.e. top menu items = #CC0000 (I don't want the submenu items to change with this )and how I would do it for the items in the submenu (without effecting the main top ones)

(3) How can I get the the whole submenu to move down? Right now when you hover over it, it covers the top menu items, I'd like to get it so the drop down red line lines up with the thin line below it.

url: http://tinyurl.com/lxtd849

Your help would be much appreciated.