অমাত্য অজাতশত্রু (Amātya Ajātashatru)@MyExcellencyAJ
Spirit colors. Long been explained in Hindu tradition.
1. White is the color of sattva because it reflects all light, showing selflessness, purity and wisdom.
2. Red is hardly the color of anyone's skin in India. It is the color of rajoguna - passion, blood, love, bravery, violence, rage, etc
3. Yellow is the color of wealth, crop, gold.
4. Black is the color of tamoguna
The Mahabharata, which you quoted, itself makes this amply clear through Bharadwaja's question that these "varnas" are not skin color. Bharadwaja says: "colors are seem among all the Varnas, that desire, fear, greed, grief, anxiety, hunger and toil prevails over all humans". Clearly, colors are assigned to gunas or qualities.