HI hi have a big problem with crome that I can't solve

I have tryed to change a lot of css, but never, I can't solve it

The problem is with crome and safari, with firefox work well!!!

please help me!

Please look at the top of the slide, with crome or safari you can see a big grey row, how I can to delete it? I firefox work well! 

http://www.virdemlux.com

Dnn 6.1.5

thanks a lot

Fabio