How to add and link a button to transparent box on home page

Site URL: https://ptepr.squarespace.com/

Hello, hoping someone might be able to help me :) I am working off of the Hatch template. I inserted a code box to get a transparent square, text is in but I cannot figure out how to add a learn more button inside this box, and I'd like to link it to the about page. The template is making the button appear on every side of the box except inside. Does anyone know what code might work for this? I really appreciate any help with this. 

<a href="https://beaverhero.com" style="background:black;color:white;font-size:20px;border-radius:10px;">Button</a>

I just added a blog post that will help you! You can check it out at rebeccagracedesigns.com/blog/add-a-transparent-background-to-text-and-buttons-in-squarespace