Sending slider back

http://173.254.28.95/~faceyour/

I’m trying to get the submenu to display over the top of the slider. I’ve tried adding z-index:-1; into the php for the slider. It does send it back, but the slider stops working. I’ve also tried adding it into the css for the slider too but it’s had no effect.

Please let me know if there is any more information that I need to add.