Thank you for advice. This revision of the website is a stub, it does not contain any useful information, just some general words. It will be heavily reworked soon.
Also, I will add the comparison table with Syncthing, BTSync and some cloud storages, like Dropbox.
Have you thought about just not using the phrase "zero knowledge" at all?
I don't use it on GitHub page. It updates more frequently than the site. The next revision of the website will contain a new motto, but I have to make a new motto first.