How do I change the color of the menu button in responsive mode?

I am using the option to "Use button to open menu" on the mobile editing screen.

The I want the button colors to match the logo colors on display (#01628D) and hover (#E09832). Right now they are light grey and a darker grey (hover), and I looked at the css and cannot figure out how to change it.

I tried adding "Responsive Menu Trigger" and "Responsive Menu Bars" from the list of available element selectors, and then added the color: lines of code below that, and it did not change the color.

How do I fix this?

Thanks.

Tim