Z Index Sub menu issue

The sub menu is under the content in the row on the child pages. I set the Z index of the sub-menu at 999999. I’m using Divi, default settings. How can this be resolved?

• This topic was modified 8 months ago by barkingbird.
• This topic was modified 8 months ago by barkingbird.

The page I need help with: [log in to see the link]