First, the sense of girlhood actually comes more from the mentality, and the mentality biased towards girls will give people a sense of girlhood.
In fact, I personally think that the girlish feeling mainly comes from the first impression between people, that is, when we first saw Qin Lan, we had already determined her image. When facing the camera or some interviews, she will subconsciously show the appearance of a little girl who has just stepped into society, and even some small expressions are the same. Looking at a 40-year-old woman, there is a sense of sight of a delicate little girl. Perhaps it is because of this little girl's mentality that people feel that she is still a girl although she is 40 years old. Coupled with some clothes, it will make people feel that she is really a girl. After all, she is a beauty herself, and it will be beautiful to dress up a little.
Secondly, apart from mentality and appearance, Qin Lan's girlhood is probably maintained by modern technology.
However, I think Qin Lan should use some modern scientific and technological means to maintain her face, because no matter how a 40-year-old person maintains her skin every day, it is inevitable that her skin will sag under the action of gravity. However, Qin Lan's face is tight and has few fine lines, which obviously does not conform to the routine of the actor. After all, ordinary people will grow old when they go to bed and eat on time every day. Even if she stays up late filming and doesn't eat on time, she can't keep in good condition. Therefore, the maintenance cost of this face should not be affordable for ordinary people. Coupled with some modern technology, injections or other physical therapy, this girlish feeling will be presented.
Finally:
Qin Lan really broke the stereotype of a 40-year-old woman. Who would have thought that a 40-year-old woman would be such a girl!