Are the 24 solar terms solar terms or Gregorian calendar holidays, which always comes from?

The twenty-four solar terms are defined according to the position of the earth in the orbit around the sun and belong to the solar calendar. The earth revolves around the sun for 360 degrees, which is 0 degrees at the vernal equinox and 15 degrees at Qingming. After that, every 15 degree is a solar term, and its date is basically fixed in the solar calendar. Twenty-four solar terms are the originality of China's calendar method and one of the brilliant achievements of China's ancient science and culture.