Create a disappearing menu in Antique Modern theme

Hi,
is there anybody who really can help me?
I want to create a a disappearing menu like in the screen shot i made and posted, but I wanna do it in the Antique Modern theme.
Don't tell me to use nice menu, coz' it's not useful for my goal.
I'd like to recreate something like this:

http://www.beatall.it/ziopaul/shot.jpg

I mean, the menu should appear under the blue botton.

Hope to read you soon.

Cheers