Drop Down menu Issues

Hello !

I am facing some issues with my drop down menu.
what i am “trying” to do is when you hover the menu, it dropsdown directly, but it is not working …
i need to click on the menu first, than it drops down.
have been trying and trying, by modifying the css, but without any success.
It is a Joomla template that i modified, but i am no CSS expert, managed so far to find my way using Google, but for this issue, it seems really easy on the help tutos i found, but when i try to apply it to my css, nothing…
I really need your help, so please could you take a look at my site and help me out ?

Site adress : http://wwww.acte2.be

Many thanks