Card font defaults to "Arial Rounded MT Std" where available, falling
back to the Google Font "Varela Round" (loaded automatically).
Data (events, recipes, meal plan, meal templates, suggestions, weather,
countdown, reminders) is polled every 60 seconds while the card is
connected; the Chores/Rewards/Goals/My Chores/Routines board cards poll
the same way. The backend poller (reminders, event alerts, chore due
reminders, recurrence resets, Daily Digest) runs independently on its own
schedule (default every 5 minutes).
HA silently skips (rather than errors on) a service call targeting a
todo/calendar entity that doesn't exist — the card checks entities
exist up front and surfaces a visible error instead of failing silently.