Read and unread mail colour contrast

1

Can you increase the visible contrast beween read and unread emails?

2

Possible modifying a theme in the Theme editor might do that for you.

(Design your own Theme)

https://www.emclient.com/blog/design-your-own-em-client-421

Also how to better Highlight UnRead Emails?

https://forum.emclient.com/t/how-to-better-highlight-unread-emails/67945