Turn Nav Bar Opaque

My site: https://www.eaglerockadvisory.com
My theme: Honma

The top menu navigation bar is transluscent. On the home page, that’s not a problem because the top of my header image is white, making the nav bar appear grey.

But, when you click on any other pages, the header image is scrunched down and forced up into the nav bar, making it look sloppy. I want to make the nav/menu bar plain grey on all pages as it is on the landing page.

I’ve combed through the editor looking for ways to do this, but I am spent. Any help would be appreciated.