Can't load css that filename start with underscore in node_modules

[ippachi]

Hello guys.
I tried using icheck in my hanami project by the below settings.

# apps/web/application.rb
assets do
  nested true
  
  sources << [
    'assets',
    'node_modules'
  ]
end

# apps/web/templates/application.html.erb

<%= stylesheet 'icheck/skins/all' %>

But some files are not delivered to public/assets because 'icheck' is importing CSS that filename starts with an underscore.

I think this code excludes css and js start with underscore.
Is this necessary?

If this is necessary, How do I load a file that starts with an underscore in node_module.