Could I be 100% Ashkenazi Jew, if i look sephardic?

This sounds wierd, but to my knowledge all the way back my at least to my great grandparents on both sides I am totally Ashkenazi, yet I look verfy tan. of course it doesnt help that I have grown up in southern california, yet it is a natural tan, and I am darker than my friends that are mexican and Egyptian. Can someone explain to me if this is possible. of course I know that it is virtually impossible to answer, but I am looking for some grand enlightenment.