This is actually great. Thanks for your help so far.

1. The header color changed on all pages except the blog page. Do I need a different CSS for that one?

2. The search option that I am referring to was done by going to Admin Panel > Appearance > Customize > Theme Options > Menu Options and selecting Search in Primary Menu. All the other ones are set to their default values and this still does not change.

See here https://prnt.sc/vupzze for what I’m talking about.