From the end of the Qing Dynasty to the present, what are the four main famous skill schools of Beijing kites?

Beijing kites have a history of more than 300 years. The shape is well-proportioned and the workmanship is exquisite. There are five basic forms of Beijing kites: hard bladder, soft bladder, row, long string and barrel. The craftsmanship is roughly divided into four items: tying, gluing, painting and spinning. From the end of the Qing Dynasty to the present, there are mainly four famous schools of techniques: First, Jin Zhongfu, whose works are bold and rough, with strong color contrasts and a very good farsighted artistic effect. It is not only loved by the old kite fans in Beijing, but also the palace mostly likes to use Jin's works. The "black pot bottom of the Fire Temple" refers to the "black sand swallows" sold at the kite stalls set up in front of the Fire Temple on Di'anmen Street by several generations of the Jin family; secondly, the kites of the family name of Ha, which is known as "Kite Ha". The second is the kite-making family of the name Ha, known as "Kite Ha". The first kites were made in the Guangxu period of the Qing Dynasty. The Ha family has several generations of artists with comprehensive skills, and the kites they make are all high-class silk products with rigorous material selection, solid and flat skeletons, and exquisite paintings. The varieties of kites include: Cloud Dragon, Five Bats, Hundred Bats, Cloud Bats, Nezha, Liu Hai, Dragonflies, Butterflies, etc. Among them, the "Thin Sand Swallow" is the most famous. Another major feature of Haji kites is the accuracy of wind-eating power, making different kites according to the size of the wind; thirdly, Kong Xiangze, whose kites are modeled after the artistry of Cao Xueqin; and fourthly, the painter Ma Jin, whose works have a strong literati temperament.