Luigi was at an entrance of Nintendo Museum with Mario who was "a face of Nintendo".
Red overall, Luigi are a white overall and green clothes on the clothes that Mario is blue in those days.
(Clothes of Mario become brown, but, concerning the number of the bits, it is originally blue.)
Overall which is blue on the clothes that Mario is red, Luigi are the overalls which are purple on green clothes now.

Mario,Luigi©1985 Nintendo