Code to move button on mobile

Site URL: https://strawberry-iguana-rweh.squarespace.com/config/

I know this isn't ideal, but I have text imbedded onto an image, and have the image set as the back ground. 

In desktop view the button looks great, but in mobile view, I can't seem to fix the spacing. I don't want to change the spacing on desktop, only when mobile is a concern.

Is there a code I can implement to fix the issue?

Your site is private. Can you setup password & share url again?