Color Area with header on all individual blog posts.

Hello,

I created a custom landing page for my blog that has a color area with a special heading in it.
This is the page: https://www.epkdesign.com/doescher/blog/

I would like that color area with the blog special heading to be on all the individual blog posts and category pages:

https://www.epkdesign.com/doescher/blog/category/blog/extraordinary-customer-client-service/

This is a redesign of an existing site so there are hundreds of blog posts.

How do I do that?

Thanks so much for your help.