Easier Time Editing Codes

Hello HB Themes Team!

I am a new user and I gota tell you, I LOVE your service and the quality of your products! Much better than those that claim they are the ultimate etc. Now I had couple of questions if you do not mind answering.

1. Setting colors has been hard for me as in the style sheet I did not
know which one to change. Even with google inspect it’s hard to find
it, any tips? I have this issue right now. My site is all black so I
must have my text white like the tags (attributes) however this also
changed the commentor’s text color and such. Any way to fix it?
http://prntscr.com/47b0be

2. Is it possible to have a category filter on full masonry blog page
or even add stuff before it?

3. can you give me tips on how to find the location of the pieces of
the theme? Like for example, I spent 30 minutes trying to look for how
to change the Read More button on blog teasers……. I still cannot
find it, I looked in multiple php files. Any tips for future and this?