The Santa Claus hat colors of white and red are in my opinion not for granted.
Why?: White is Spiritually associated with righteousness. While red danger and death. Now, the lower and upper parts or extremities are white, and the middle part between them is red.
The lower part which larger which and white depicts that all are borne righteous. Then after birth as one grow. is exposed to dangers of the world due humanity sins hence red color resulting to a few triumphing and ascend into heaven righteous, thus the upper part is smaller and white to symbolize this.