How to make blog summary page different palette than blog posts?

Site URL: https://apple-drum-7nk8.squarespace.com/perspectives

I'm trying to figure out how to make my blog summary page one color palette (dark minimal), and my individual blog posts as my light minimal palette. I've managed to adjust simply the background color of the summaries page, but can't manage to adjust all other aspects of the section. Any ideas here? Page is at: https://apple-drum-7nk8.squarespace.com/perspectives and password is: p3akt3ch

Thank you!!! 

Sorry for the clog. Finally figured this out. See code here if helpful ( I know I've seen other incomplete/ unsolved threads with similar questions) 

.blog-side-by-side{
  background-color: #1E1E24 !important;}

.blog-side-by-side .blog-title, .blog-excerpt, .blog-date{
  color: #ffffff !important;}

.blog-side-by-side .blog-meta-primary{
  color: #ffffff !important;
}

And then depending on your blog style, replace .blog-side-by-side with whichever blog type is relevant: