Change Heading Background for Category Breadcrumb

• Hi, I am new to the Astra theme.
• I created my first website and cannot figure out how to change to background of the header of category sites that are automatically generated. I attached two screenshots to make clear what I mean (3. is the background that is white but should be gray).
• Demo: https://letstalkabouthaptics.com/category/automotive/

The page I need help with: [log in to see the link]