What does vernal equinox youth mean?

Describe those who are young, energetic and full of vigor. According to relevant information, "Youth at the Equinox" is an online buzzword, which refers to young people around the age of 20. This word comes from the "vernal equinox" in the traditional 24 solar terms in China, which represents the season when spring is equally divided day and night and everything is revived, while "youth" refers to the younger generation.