Index page won't crop in mobile

Site URL: https://www.andyshiels.com/

Hi Guys.

I'm having an issue with my landing page on mobile. It's an index page that doesn't scale down the type properly. I've spoken to Squarespace and they said it's a bug with 7.1, specifically related to an issue with paragraphs and heading not scaling to mobile on their end.

But it can be fixed with some custom CSS. Any ideas?

Here's the page — www.andyshiels.com
Screenshot also attached. 

Thanks in advance!
Andy