Where can I get the css file for ruby plug-in?

[KITAMURA-Tomihiro]

I wanted to use the ruby plug-in for Trumbowyg, but I could not find css file for it that is explaied in "Demos | Trumbowyg: A lightweight WYSIWYG editor | Alex-D / Alexandre Demode」https://alex-d.github.io/Trumbowyg/demos/#plugins-ruby.

Could someone tell me where to get the css file?

[Alex-D]

That's an error in the documentation since there is no custom CSS for the Ruby plugin.