changing element mobile header color.

I have a different header (created through elements) on my home page than the rest of the site. In my element (called front page) I set the checkbox "navigation colors" to checked. I have set the colors there.

The problem is that I can't seem to figure out how to change the background color of the mobile menu.

I've tried using the off-canvas colors panel as I've seen suggested but that doesn't change the mobile menu background for any pages whether it's the front or not. (my off canvas panel is off btw)

How can I change the mobile menu background to white?