How to change page title background color

I’m very new to WordPress, and I’m using the Clear Style theme.

https://texinstexoma.com/amenities

I’d like to change the background color in the box that shows up behind my page titles (ie. on the page above, there’s a light gray box behind “Amenities”). I’ve created a child theme and am making my style changes there, so I think I’m headed in the right direction with all of this, but sometimes there is an element I can’t find, and this is one of those times. Help!