Hello 
!
A little doubt I have,
The other day I was looking for a way to customize some colors of Links and background in emails, however at that time I couldn’t find an option for it and I tried resorting to CSS and such
spoiler: it didn’t work (I still don’t know how this template goes of e-mail) 
However, wanting to change a site configuration I found that these 3 options are found in the “general site” configuration (I changed them recently)
Personally, I think it should go in the “Email Style” section 