Dropdown menus not working

Hello everyone,

I have a slight problem with my WordPress which was running flawlessly ( almost ) for many years now and can’t solve this one by myself :

My dropdown menus are down. I tried ton change my theme and go back to Twenty Eleven to test but the menus are still broken. I updated my theme : no more luck. I tried a plugin to keep jQuery updated but still no luck.
Do you have anu clue ?
Thanks a lot in advance.

Y

https://www.zboo.org