I second the request to make the site responsive. When I load the page the CSS constrains the main content to 560px and the whole page is constrained to 940px. Here's how it displays on my system:

https://i.postimg.cc/zDMD9nYD/Simon.png

Your tastes are your own, and there is an argument for just filling the window, but you won’t find a typographic authority that advocates setting body text much wider than that (and I would agree with them).

Can you take a screenshot of some other site that is wider but has a comfortable reading width for you?