Stack order works differently in FF than Chrome?

If you hover on Services the submenu appears behind the video (Chrome on a mac). In Firefox it sets the submenu infront of the video like it should.

I have set a z-index that work over images, but for some reason tried setting z-indexes to no avail. The fact that FF (and Safari) works fine without the z-index seems odd to me.

Don’t have too much knowledge with CSS stacks, so I’m sure it’s something trivial I overlooked.

Thanks in advance!

is this perhaps an iframe problem??

Found Problem!

I have to add a snippet to the iframe html…

This page explains…still weird though.