What does it mean when the lower edge of the rearview mirror is parallel to the yellow line during reverse parking?

[McJourney]

When the lower edge of the rearview mirror is parallel to the yellow line during reverse parking, it means that you should focus on the side of the car body closest to the boundary line. The side of the car body farther from the boundary line will appear parallel to the yellow line when viewed in the rearview mirror. Below are some precautions for reverse parking: 1. Reverse from the left side: Whenever possible, choose to reverse from the left side, as it is easier for the driver to observe. During the reversing process, first look behind, then pay attention to both side rearview mirrors. 2. Observe the rear situation: Before reversing, check the situation behind the car, estimate the reversing route, and determine whether the front of the car will hit any obstacles during reversing. Especially when the steering wheel is turned significantly, the turning radius of the car's steering wheels is larger than that of the rear wheels, and the front of the car will swing outward more during reversing. Be sure to avoid scraping or hitting the front of the car.