How to load css in public files

On my project i have following routes (routes.rb)

resources :main, path: '/' do
    collection do
      get 'about'
      get 'blog'
      get 'resources'
      get 'contact'
      get 'projects-and-tutorials'
    end
  end

and these routes are loading files from public folder like about.html and contact.html, right now no css file is loaded on these pages.

I have created a css folder under public folder and will load css file from there on these public pages but i am not sure if it is good to go with

should i load css files from app/assets/stylesheets or there is another way to load css on public files ?