As for as I am concerned, racism is more complex than following a black-white stereotype.

Correct.

So a white can call another racist if they consider each other of different sects or tribes, that sounds more like tribalism but they all the same to me.

The are not the same. What you've described in that sentence are have their own names: sectarianism and tribalism. Both distinct and different from racism. Racism demands that you're of different races by definition.

I don't have to read about racism as I am stating racism as any form of stereotypic judgement in this case.

You really do, as you don't seem to understand the meaning of the word. Incorrectly calling someone a racist by assuming they are racist based on the fact that they're white is not being racist, it's levelling false accusations. Being racist is a different thing, and using it to describe name calling trivialises it's impact. Racism is not a generic term, it has a specific and defined meaning. That's all I'm saying.