Everything you write is encrypted in your browser before it's saved. No one else can read it — not the server, not the admin. Only you.
Your email
Invite code
Choose your passphrase
Read once, carefully: your passphrase is the only key. If you forget it there is no reset — not by anyone. Next you'll get a recovery code; save it somewhere safe. It's your only backup.
Save it in a password manager or write it down. If you forget your passphrase, this is the only way back. Lose both and the data is gone forever — the price of real privacy.