Change color of POST title in Hatch

I am helping my friend customize Hatch for her Interior Design business and I can’t figure out how the change the Title of the Gallery/Post. Since I changed the background color to black, it defaults to grey so making it hard to read. I would like to change it to green as some of the quotes inside the various galleries/posts but i can’t find the code. I am a designer, not a programer so please be kind ?? I have solved tons of issues with awesome answers from this forum but I can’t seem to find an answer to this issue.

Thank you!

Here is the site:
https://www.hueofyou.com