Secondary menu background image styling

Site url in private reply.

I am trying to apply a specific background to the secondary header menu. I have set the background, but it is sitting on top of the menu/hiding it. I have tried applying a z-index to force the actual men/links forward, but it’s not working. To what class or id would I apply the z-index to bring the menu/links to the front? Is there a better way to do this that I’m not aware of?

Thanks for any help– still love this theme! :)
Angie