Does Q in Star Trek always have blue lips?

A quick search of Q images reveals that he doesn't always have blue lips. It appears he tends to change his complexion depending on the role he is assuming.

That said, the picture below with the blue lips might be considered Q in his natural state, so perhaps they are indeed blue. As to why, I have no idea other than the fact that he is an omnipotent alien, and perhaps that is one of their features :)

In the Star Trek Voyager episode "Death Wish" which features 2 members of the continuum, both have slightly blue stained lips, indicating a racial trait.

It's a little hard to see in the image but it's unmistakeable when watching the episode

I never noticed his lip color: The specifics of skin, hair, and eye color are especially superficial in the Star Trek universe.

I expect any unusual coloration is to reinforce a being's other-worldliness. Q is definitely not human and should not be confused as such. He may as well have a diagonal purple mohawk.