How can I encourage husband to be more positive?

JJ

I feel like my husband complains about EVERYTHING and EVERYONE. His boss, the guy that stood behind him in line, grocery shopping, birthday parties, swimming, going for a walk, work, co-workers etc literally anything and everything. It drives me nuts. But I feel like if I say something he’ll feel like he can’t vent to me, which I know he NEEDS to do. Buts it overwhelming. I’d like to just say “if it’s not a positive comment I don’t want to hear it!” 😂😂 but I know that won’t help and he’ll probably just go mute. How can I encourage him to be more positive and complain less but not sound like I’m putting him down or like he can’t come to me with an issue?