Why did the calligraphy of Yuan Dynasty present a fresh and elegant atmosphere in just a hundred years?

In the short hundred years of Yuan Dynasty, under the influence and promotion of Zhao Meng, a large number of well-known calligraphers appeared one after another. Some of them are friends of Zhao Yu, while others are his students. Throughout the history of calligraphy in Yuan Dynasty, it can be roughly divided into two periods. In the previous stage, with Xian Yushu and Deng as the core. The latter stage is represented by Zhao's students Kang Lizishan, Zhang Yu and others. Although their artistic styles are different and their achievements are different, they basically learn from the Tang Dynasty and the ancients, paying attention to the sharpening of skills and the inspiration of charm. Through their efforts, the calligraphy circle in Yuan Dynasty presented a fresh and elegant atmosphere.