Why does the length of the day increase in spring and decrease in autumn?

We all notice that the day decreases in winter and increases in spring. But not everyone knows why this is happening. The fact is that there are several lighting belts on our planet. If we were in the first, at the equator, then day and night would be approximately equal. But we are in the third in temperate latitudes. Here it turns out that due to the fact that the Earth revolves around the sun and around its own axis, the amount of sun rays and the angle of their arrival is uneven throughout the year. The higher the sun, the longer the day and vice versa.