to red for the menu entry currently being hovered. While you're at it, make the background of each level of submenu slightly darker.

Rework the styles from the second half of the project to make sub-submenus pop out to the left of their triggering menu entry instead of to the right. To look as good as possible, right-align the text in the submenus, but make sure it does run up against the right edge of the submenus. Also, you'll need a new arrow graphic. (Try flipping submenu.gif horizontally in a graphic editor like Photoshop.)