Tips to get baby to take longer naps?

Athena

I have a 12 week old who basically refuses to nap. He hardly ever naps longer than 30 minutes at a time. He is tired again shortly after waking up, and then is almost impossible to get to fall back asleep because he is over-tired. I am trying to not have him be dependent on nursing to fall asleep, but sometimes we spend over an hour trying to get him to fall asleep to then only stay asleep for 20-30 minutes. At times I will let him fall asleep while nursing just so he can get a decent nap, but even then he sometimes wakes frequently and doesn’t actually fully fall asleep. He sleeps really well at night, but naps are practically impossible.

Any tips to help him nap better? We always swaddle him and use white noise, and his bassinet is in a pretty dark room.