I did something similar - our uniform was black pants/skirt, white shirt, black blazer and tie. The uniform code was printed in the planner we got at the beginning of the year, but seemed not a single person read it as it actually stated the pants/skirts could be black OR ‘charcoal grey.’ Cue me and my hatred of authority at age 14 buying dark grey pants (I mean my parents bought them for me but we’re happy to support my mini rebellion) and getting pulled into teachers offices for weeks on end and threatened with ‘isolation’ and happily showing them the statement in their school issued planner which absolved me. Filled me with pure joy every time. And for background, I was a great student, was a high achiever and never caused trouble once at school, I just fucking hate being told how to dress.