Offline mode stores your scores and chat keys only in your own browser. If you create an account on a Neon-Pulse API, your username, a salted password hash, scores and play statistics are stored on that server. API keys you paste for Groq or Gemini are kept in memory and never saved. Contact messages go to the site owner by email or to the API inbox. The site sets a secure refresh-token cookie only after you log in.