I'm writing this help thread on my phone, which suddenly is the only way I can access the website. On my laptop - on all three of my browser apps: Safari, Chrome, and Firefox - the layout is gone, the images are gone, and the only links that work are the ones in the menus. These, unfortunately, are covered by a layer of text and broken-image icons, that slides up and down to my mouse scrolls, but which can't be clicked on. I will attempt to upload a screenshot, fingers crossed.
Has ANYONE else heard of anything like this happening to anyone? My other regular Sims 2 websites- PlumBobKeep, etc.- look fine. I know I've had a lot of wacky issues in the past, some of which are related to my being a Mac user, but this one takes the cake. I don't know what to do. The prospect of using my tiny phone screen to look for CC, download it and email it to myself is almost too painful to contemplate.

I've had it happen on occasion if the internet connection is a bit iffy or if a site has loading issues, or something of the sort, but it usually tends to clear up when whatever is causing it clears up. MTS is currently working fine for me.

Have you checked your internet connection (especially if you're having trouble with other sites or web pages loading in general)?
Have you checked your browser settings? Sometimes if those have been changed, you can get loading issues with some sites ("only HTTPS"/stricter tracking/etc.).

Have you tried the "Bootstrap - Bluefish" style (you can change it down in the right corner. You might be using an UI that doesn't works as well for you at MTS - Bluefish is the one I'm using, and I'm currently not having any issues, so could be worth a try to switch).

Also delete all of your browser caches, history and cookies for MTS and login again.

I will definitely try all those things, although I've so far been unable to click on the "bluefish" setting... it's on the part of the page that's disabled in my bizarro world. I was able to switch to the "old style" view, but that only made the page less interesting to look at, not more functional.
And... MTS is the ONLY website affected like this, seemingly. I've had a slightly similar issue before on TSR, where the download links didn't work, and also for the Box.app site; I'm able to work around both by using my phone, although it's kind of a drag. But those are nothing like this. If I could post a video somewhere here, it would better illustrate what's happening. It was literally working one day, and not the next. I'm very sad, and anxious to find a way to make things right again.

I've had that occasionally on my ipad but it works fine on my computer. Sometimes its there and then it goes back to normal next time.

Maybe the server "static.modthesims2.com" became inaccessible due to misconfigured ad block, an error on the DNS server, or an issue with an SSL certificate. It sometimes happens that font "styles" on websites do not load and it resolves over time.

Update... nothing much has changed really, but here's another piece of evidence to consider. Going back in my browser history, I found an instance of the page where I wasn't logged in, and it loaded normally... sort of. But as soon as I logged back in, it reverted to the goofy double layer look.
So make of that what you will...

Does it make a difference if you hard refresh (shift+cmd+R)?

Alas, no - it's the same told same old. Surely it's telling, though, that it only happens if I'm logged in... I'm not sure what that means, but I think it must mean something.

Make a new thread here so that the site owner can advise:
https://modthesims.info/f/24/

Roger, Roger.

What's your vector, Victor?