Green cm?

So, I've had slightly greenish tinged cm for 3 cycles now. Like, you know how when you've got a cold and you sometimes cough up mucus? It looks a little like that. As far as I know, nothing has changed or been any different.

No itchiness, no pain, no changes in my cycle. Everything else is totally normal and I feel fine. I'm absolutely sure that I don't have any kind of infection.

But what could possibly make my cm that color? It's really not super noticeable or bright, but there certainly is a green color to it if you look. I'm not really concerned, just mostly curious. Could it be a diet thing? Vitamin deficiency? It's super odd.