

If we’re talking about online editing, Collabora has web editors based on LibreOffice but with a modern UI: https://www.collaboraonline.com/
They are really great and can be self hosted (e.g. with Nextcloud).
For offline editing, as already mentioned, LibreOffice has an optional ribbon UI and OnlyOffice looks pretty modern as well.





What do you want to host?
If it’s a simple text-only/Javascript website, you can host through Codeberg/Gitlab/Github on a custom domain free of charge.