How can i convince my parents to let me get acrylic nails and higlights.?

im 13 and going into the 8th grade. im also very responsible and do my chores everyday. i went to the local "spa" my mom got ubberly fancy acrylic nails and totally dyed her hair! i ask my mom if i could get the simple acrylic packet nails (much cheaper then hers) and she said no. when she got her hair done she totally dyed it all. i asked if i could get Highlights she said no. i asked her why and got no answer....i don't know why she wont let me...she said when you dye your hair you never get your original color back. i did myResearchh and that is in fact true. but then i told her that i only wanted to get the ends done which would not effect my entire hair color. i alsoresearchedd that. i still have no idea as to why i cant get acrylic nails! can someone please give me some ideas as to how i can convince my parents to let my get those to features done. also can someone give me some possible reasons theywouldn'tt let me do those? thank you so very much <3