team color swap

[vanilla]

so ,i saw this mod on game banana that swapped the team colors , and instead of red vs blue you had black vs white . but when i took a peek at the comment sections people were saying how team white was way too white and the mod description said that someone could do it better . so here i am , trying to learn how to change the colors of every single class, weapon , miscs. do any of you here know where do i even start?