Current Menu Highlighting - need help

[shoshanaz]

What is the magic css formula for having the current menu item highlighted?

For example when I click the "staff" menu item I would like "staff" to have a different css style applied to it.
My menu has a class of mainmenu applied to it.
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found my own answer: here it is in case it saves someone else time...

#active_menu_mainmenu { color:#blue;}