Cold at night?

Now that my son is no longer sleeping in the rock n play at night, I'm worried about him getting cold. Every night so far his hands are freezing when I get him to feed him. 🙁 His torso seems warm, but I've read conflicting things about whether or not cold hands=cold in general. He's wearing a short sleeve onesie, socks (if he hasn't kick them off, and a long sleeve fleece sleep sack. Thermostat is on 70 and it's been 30s to low 40s here at night.

Idk if I should maybe add thin pants under the sleepsack or something else...