How to change height of site title and tagline over main image

I am helping someone build their blog using the 2017 wordpress theme. I am attaching a screenshot of the issue I am trying to figure out. I found some CSS that moves the big “The Seforim Blog” up in height to where I want it to be. I also want to move the “All about Seforim etc” up in height as well but any CSS i try moves both the big title and this line. (Seforim are books in Hebrew btw). Here is a picture: pic of site

Thank you