[ Family ] Open Question : my parents are putting very strict restrictions for my clothes.?

hi i am egyptian and a muslim, i am living in ksa we are wearing here 3abayas and scarfs , my parents are so strict in the issue of clothes,every thing for them is so short and so tight. what can i do to make them understand that most of people wear that way and by the way i am wearing very moderate clothes,and i have another problem:from maybe 2 months i went with my friend and her family to a place and there was a boy there and i take of my 3abaya and scarf i was wearing a normal t shirt and pants but if my mother knew this she will be very angry. now she will come with me the same place and the same people will be there but she wiil let me wear long sleeves and a scarf and i will appear very contradicing. infront of my mom i wear polite clothes and behind her i wear what i want help me what to do note:she wasnt with me the first time.