Why are the 24 solar terms, totaling 360 days and 365 days a year, roughly balanced with the solar calendar over time?

Let me answer you. Let me define it first. The twenty-four solar terms are divided according to the position of the sun on the ecliptic (that is, the orbit of the earth around the sun). So strictly speaking, the interval between solar terms should be 15.2 days. But people's general definition of the sky is day and night, so the interval between the 24 solar terms is usually 15 days, but sometimes 16 days. Count it on the calendar!