Let me add my experience in of this.
DD who is v light redhead/auburn wanted to be dark. So we did it. She's far too pale for it but to be honest it wasn't bad actually. That wasn't the problem though because, of course, within a year she then wanted to be blonde.
So we went blonde. Now that takes an awful lot of maintenance, cost (kinda had to be done at the hairdressers), many wrong turns with hairdressers who didn't really understand colour and she had her hair turned green three times and her hair was in dreadful condition.
Then she wanted pink. I had no problem with this as it's non-damaging, can be done at home, not expensive.
In amongst all this, after the blonde she went to a bob (which looked gorgeous on her) and now she wants to go back to long hair!
All I'm saying is, dark colours take professional efforts to remove when she (inevitably) realises she doesn't like it any more and simply must change it - again. And that this may repeat over and over.
If you've plenty of cash to splash, great, if not, it will drain your finances trying to keep up with every whim and change of mind. Added to which, a teenager box dying at home is like letting a toddler loose with a permanent marker - it gives me the willies.
Think v carefully because it's not just this colour, it's the next 3 or 4 changes after that that you need to think about.