The two themes are exactly the same. I just changed the name, but their effects are different. The CSS file works, but if you modify the CSS file now, the theme will not be updated。
Sorry, my fault. I use tutor. The version is 13.2.0. There are two same theme files under my theme folder. But when I run tutor dev start LMS, tutor dev settheme mythemename1, and tutor dev settheme mythemename2, these two themes with the same name have different effects. Thank you