Why does the Yellow Calendar avoid burial?

The solstice in winter is the shortest day. According to China's theory of Yin and Yang, it is a cathode day, from which the yang spirit comes. So part of this day is used for burial and sacrifice, so the winter solstice is a good day for burial. There is another traditional custom from the winter solstice, that is, burying the deceased relatives on this day. In some places, you can't be buried anytime and anywhere on the day of burial. Traditionally, it can only be buried in the winter solstice, so it is not appropriate to look at the Gregorian calendar only. Don't worry! The solstice in winter is a good day for burial!