Changing Headline color and Removing Categories Titles

Hi Can anyone help me to Change the Sticky header color ( if you scroll down the header becomes a topbar) of this blog .

https://www.Going2natural.com

Also I had to redirect my pages to there categories for up to date posts now I’m unable to get rid of ” Posts in Category..” heading.

Also we’re using the Evolve theme.

Thanks for any help.