Website’s suddenly a mess on mobile devices

I just discovered that while my website operates fine on my laptop, it’s a complete mess on smartphones and tablets. In the past, I have verified that it works on other platforms, but it’s not something I check regularly, so I’m not sure how long it’s been this way. 😳

This issue can be reproduced by accessing my website (www.spiritwright.com) from a smartphone or tablet (at least iPhones and iPads … I don’t have access to other platforms.) I use the Hestia theme and keep all software and plug-ins up-to-date.

I’m a non-technical user running a website as a public service so am feeling completely out of my depth. Help … ? 🙏

The page I need help with: [log in to see the link]