When did the day and night turn upside down?

The length of day and night changes with the seasonal changes caused by the revolution of the earth!

Spring begins at the vernal equinox and divides day and night equally, then the days begin to get longer and the nights begin to get shorter.

In summer, the summer solstice is the longest day of the year, that is to say, from this day on, the day reaches the longest season.

At the autumnal equinox, day and night begin to divide equally, then the days begin to shorten and the nights begin to lengthen.

The winter solstice is the longest night in a year. Until the vernal equinox, the night is long and the day is short.

So, back and forth!