How long do notes stay offline?

How long do notes stay offline?

When I click a note its title color changes which seems to indicate it's offline. How long does that note remain available offline?

Is there any way to "pin" a note, favorite, or folder specifically for offline access?

Seems like the only offline option is to sync a whole workspace (or maybe the whole database?) which is a lot to sync and a lot of data I don't need in there.