Header Text Outline

I apologize if this question is misplaced, but I’m hoping someone can tell me how to add an outline/shadow/etc. to text in Header 1. I’m restricted to using a background with both light and dark colors, and it would be helpful if I could use a light colored title font with a dark outline (or something similar). Please see attached screenshot (header 1 title is in yellow, indicated by red arrow).

Best,

Mike