When the earth is closest to the sun, why is winter the solstice?

Winter is the season when the sun is closest to the earth; Slight cold is the closest solar term to the earth. So, why is it that the closer the earth is to the sun, the colder the weather is? In fact, the weather is not directly related to the distance between the sun and the earth, but closely related to the area where the earth receives sunlight. In summer, the sun is directly above the earth and directly shines on the surface of the earth, producing a light-gathering point and concentrating heat; In winter, the sun hangs obliquely above the earth, and the light produced presents a scattering surface, and the heat obtained naturally dissipates. Take a flashlight as an example. When you shine on the ground from directly above, the light spot is small and bright. On the other hand, the light spot will be large and weak when it is tilted. So although the sun is closest to the earth in winter, the weather is coldest. Maybe you will ask, since the temperature of the planet has nothing to do with the distance from the sun, why is the surface temperature of Neptune so cold? That's because Neptune is too far away from the sun, about 450 million kilometers, which is equivalent to 30 times the distance from the earth to the sun. Because the radiation intensity at a certain point is inversely proportional to the square of the distance from the radiation source, the solar radiation per unit area of Neptune's surface is only 1/900 of that of the earth, and the solar intensity is only equivalent to the light intensity emitted by a 100 watt bulb less than one meter away.