I have teen dds so I understand what you are saying. I have had to master the art of neutral answers
' I hate brown hair, it is vile'
A: ' I can see that you don't like it, what colour do you like?'
' I am not wearing that I will look like xxx'
A: 'okay what do you feel comfortable in'
' I am not going to bed'
A: ' okay, but we won't be able to give your phone privilege tomorrow, as we agreed 9pm'
I try to use a gentle tone without being patronising, try to avoid yelling or arguing back and when they are completely kicking off grey rock. It is so easy to reduced to a 12 year old again.
Swearing and insults are an instant phone ban in our house, and so are any comments about the way others look. Absolutely unacceptable.
We have agreed bed times, phone use and expectations around food (vegetables) and homework. It is really much easier if you simply do not engage fully when they are very upset and angry - and see it as a passing rain cloud rather than a personal attack. Just acknowledge they are upset, say you are happy to talk or comfort them and stand back.
I don't think it is anything you are doing, it is just very hard at that age. One minute they are lovely, the next an angry raging hormonal pre teen.
Try to avoid losing your shit completely, as this may scare a pre teen (The internal storm is already enough to deal with) Calm and together has been my way forward - never ever taking it to heart - go back to the toddler years of endless calm patience and allowing it to blow out pretty much.
Be glad she is developing normally