hey im tring to make some menu with slide so far its all went good

my problem is like that.

on IE = page load and the menu its shown for sec and gone - need to click the button to make the menu slide

on other hand

Firefox - when page load Menu is shown and not going away

need to move mouse over to make it go away

how can i fix this ?

here is the link to the file :

http://www.d-code.net/1.html

10x guys