What is the "literati painting" in Song Dynasty?

First of all, the so-called literati painting is the hat worn by people close to you, which can basically be equated with literati painting. After all, the authors are mostly literati. But flowers and birds and specific scenes are more important than landscapes, and the theme is secular. This is rare in contemporary literati painting. At the same time, there are many differences in technology, which should be relatively limited. Now some people think that scholar-bureaucrat painting is literati painting. Personally, this is wrong. Can be classified by subject matter, not a single category.