BB Theme separator color for responsive nav menu

Good day. I’m trying to change the default menu separator color in the BB Theme. On desktop view, it’s light gray, which is great. On tablet and mobile view, it’s dark red for some reason and I can’t figure out how to change it to light gray.

I’ve searched for previous threads with CSS code to change the separator color, but nothing seems to work.

My URL is

I’m using BB Theme with “flyout overlay” as the responsive nav layout and “right” as the responsive nav layout position.