Football home and away jerseys

Factual Questions
1

So, I had just finished explaining to my girlfriend that the home team wears white in every major sport except for football, where the away team wears white.

Lo and behold, opening day arrives and some home teams are wearing white and some are wearing dark and I look silly.

So, what gives? Am I right for basketball, hockey and baseball? Is this something new for football? And, how do they know who’s wearing what jersey if it’s not standardized?

Thanks!

2

I think the home team gets to decide which jersey they’re wearing beforehand (I’ve seen my team the Gators wear both blue and white at home), and the visitors must wear something different.

3

This thread already discussed choice of jersey colours.