Why you guys added an underline in the title of Japanese for Chinese speakers?

Hi, there. I want to say smth about the course name of Japanese for Chinese speakers. In terms of other courses for Chinese speakers, there are no underlines between course names and level numbers, say, 法语1. but there is an underline between them in Japanese course for Chinese speakers which is not so beautiful, 日语_1, like this. Please modify the name if it is possible, thx.