Change site-heading and subheading text color?

[N0NB]

I have an image for the home page that makes the site heading and the subheading a bit difficult to read as white text. I see that site-heading appears in assets/sass/main.scss in several places but did not find a color value in that area. I am completely unfamiliar with scss so I'm not sure how to implement an override in my project.

Thanks.