How do I use CSS with a ruby on rails application?

How do I use CSS with RoR? When I link externally, I'm never able to see the files. I cp'd the .css file to every folder I could think of...views, controller, template, and nothing seems to work.

What do I need to do to enable external CSS files with a rails application? I'm new to rails, so forgive me if this is basic.


Put the CSS files in public/stylesheets and then use:

<%= stylesheet_link_tag "filename" %>

to link to the stylesheet in your layouts or erb files in your views.

Similarly you put images in public/images and javascript files in public/javascripts.


If you are using rails > 3 version, then there is a concept called asset pipeline. You could add your CSS to

app/assets/stylesheets

then it will automatically be picked up by the app. (this is useful as rails will automatically compress the CSS files)

read more here about the asset pipeline


Use the rails style sheet tag to link your main.css like this

<%= stylesheet_link_tag "main" %>

Go to

config/initializers/assets.rb

Once inside the assets.rb add the following code snippet just below the Rails.application.config.assets.version = '1.0'

Rails.application.config.assets.version = '1.0'
Rails.application.config.assets.precompile += %w( main.css )

Restart your server.


I did the following...

  1. place your css file in the app/assets/stylesheets folder.
  2. Add the stylesheet link <%= stylesheet_link_tag "filename" %> in your default layouts file (most likely application.html.erb)

I recommend this over using your public folder. You can also reference the stylesheet inline, such as in your index page.


The original post might have been true back in 2009, but now it is actually incorrect now, and no linking is even required for the stylesheet as I see mentioned in some of the other responses. Rails will now do this for you by default.

  • Place any new sheet .css (or other) in app/assets/stylesheets
  • Test your server with rails-root/scripts/rails server and you'll see the link is added by rails itself.

You can test this with a path in your browser like testserverpath:3000/assets/filename_to_test.css?body=1