If childhood is sky blue - because of its purity and clarity; if old age is black - because it is the end of the long road of life. So what is the color of youth? If you know that Di Shui worked hard to expand his chest and turned into the sea, and did a few push-ups and became surging - you think, he is happy. But if you think that a drop of water has been dormant in the roaring waves for a long time, you think, she is unhappy. Schopenhauer said: "Things themselves remain unchanged; what changes is people's views on things."