What age would you allow your daughter to start shaving her legs?

My daughter is 7. She's recently become very self conscious of how hairy her legs are. It is pretty dark hair and I feel bad she's upset about it. She's stopped wearing shorts and will only wear pants or long dresses. She's asked me multiple times to let her shave but I don't know when is too early. I didn't have that problem at such a young age so I don't know what she's going through 😕