I’mafraid you can’t, but if you have an android you can just download the app and get access; once you get used to it you will see it’s even easier than using an email!
Interesting concept. It should be possible in principle but perhaps not without going through some kind of proxy (especially for access to all functionality). I can see the value of being able to engage discussion on the group pages. Might investigate this further sometime when I get a chance.