We are seeing intermittent problems logging into the game due to Steam's authentication server not responding. Hopefully this will be fixed by Steam soon.
In the meantime:
1. If you have created a password for your account, you can login via http://game.cardhunter.com. If you want to do so, but don't have a password, just email [email protected] and we can fix you up.
2. If you click "try again" after a failed login and see a panel that says "Select Card Hunter Account", try clicking on that panel and it may accept your login. This can happen if the authentication server starts responding after a series of failed login attempts.
We sincerely apologize for this problem - we realise this is frustrating for you and we're doing our best to correct the issue ASAP.