Across China, some young people are switching from jeans and T-shirts to long dresses, silky robes and black hats. They’re not cosplayers or period drama actors, but rather members of a booming movement to turn Hanfu, or ethnic Han clothing, into everyday wear. The so-called Hanfu movement has gained a large following among the ethnic Han Chinese group, which makes up more than 90% of the Chinese population. Supporters say Han people need traditional attires to celebrate their own ethnic…