need help! red/purple stems and yellow leafs

i started 3 plants 20 days ago and they have all had a redish purple hint on the stems, i transfered them into bigger pots and all of em got alot darker purple, even the veins in the leafs are purple. its pretty cold in my grow room so that might b it. but let me know if you have any ideas



sorry about the blurry pic, its a really ghetto camera

My outdoor plants always have purple stems and stalks, no worries there. My guess is cooler nighttime temperatures, or so that's what I've read countless times on here. I don't even pay attention to the purple coloring anymore as it seems quite natural to me and my plants thrive and produce, so I wouldn't worry about it. Others may have different opinions/advice.

yea i just wanted to make sure lol but thanks