When He complained to his mother Yashoda, she teasingly replied for Krishna to paint Radha’s encounter what ever color he selected, so he did. The traveling multihued pigments, referred to as gulal, remind from the story of Krishna. The night time before Holi is named Holika Dahan or "Chhoti Holi" https://www.youtube.com/shorts/hA1AxBZjUoQ