SASS CSS changes

I am playing with an install of the whoop theme. I changed the color of the header but also need to change the colors of the nave menu which is proving to be very tedious.
I looked through the css folder for the starter theme and I found SCSS files! YAY!
Upon further investigation it looks like all of the color codes are hardcoded unless i’m missing something. Is there a file that contains color variables that I’m just not seeing?

Also has anyone used the WP-SCSS plugin? I’d like to make my changes in sass in order to keep it clean and reuse existing variables but i’m not having any luck setting the correct paths.

I’m using the following paths but apparently they are incorrect.
/wp-content/themes/directory-starter/assets/scss/
/wp-content/themes/directory-starter/assets/css/