Why is the sun in the southeast and in the northeast at sunrise on the morning of summer solstice? Can you explain it?

The above picture shows the sun's position at different times from sunrise to sunset in the northern hemisphere from summer to solar day M. Where the pink cross represents the azimuth coordinates. It can be seen that:

M at sunrise, the sun is located in the northeast of the local area;

At 6: 00 local time, the sunlight comes along the tangent direction of latitude, which is due east;

At 6:00- 12:00, the sun is always in the southeast and gradually approaches due south;

12, the sun is due south;

From 12 to 18, the sun is always in the southwest direction and gradually approaches the due west direction;

Local time 18 m, sunlight comes along the tangent direction of latitude, that is, due west;

At sunset, the sun is located in the northwest of the local area;