How do you get the style of CSS file in stylesheet from the view generated by rails controller actions?

  question, ruby

I have been studying for almost a week, but I don’t understand it. Please explain?

app/views/layouts/application.html.erb
This document contains a passage like this

<%= stylesheet_link_tag    'application', media: 'all', 'data-turbolinks-track' => true %>

Css is quoted here.