Slideout menu colors

Hi, I'm trying to set up the slideout menu so that the sidebar color below the menu items is the same as the background behind the menu items itself.

I understand that I can do this by specifying the menu background color, but then the color behind the hamburger icon isn't what I desire.

In other words, I'd like for the entire header section (including the background behind the hamburger) to be red, while keeping the entire slideout menu gray.

Here are a couple screenshots to explain what I'm getting at.

https://imgur.com/a/giZDY
https://imgur.com/a/jRe9K

Thanks!