Easy to style

When you change the stylesheets of the menu you can consider these classes added by the menu script when initializing the menu.

ul.level1 

the first level of the menu 
ul.level2-.levelN
each level (submenu) is assigned an incremental class name
li.trail
elements leading to an element with the class "current" are marked with this class
ul.subMenu
when a menu is "expanded" (i.e. moved to below the first menu level) it's assigned with this class
div.initialized
the container item is assigned this class when the javascript has traversed the menu and set up events
li.expandable
elements that contains a subMenu are given this class
li.hover
when the mouse hovers a menu item with a subMenu it's given this class
li.expanded
when an elements subMenu is expanded it's given this class
li.current
this class is not added by the menu script. if you give an element this class the menu will expand to that element upon initialization