As many others have said, static html and css are your best bet for having your site continue to function.

As for having it continue to be hosted, I suggest IPFS. https://docs.ipfs.tech/how-to/websites-on-ipfs/single-page-w... So long as your site continues to be interesting, people can continue to pin replicas of your site. The domain will lokely lapse without maintenance, but the content will still be out there.