README.md in humane-rails-5.0.2 vs README.md in humane-rails-5.1.0

@@ -43,9 +43,13 @@
 
 ```css
 *= require humane-rails/jackedup
 ```
 
+```css
+*= require humane-rails/flatty
+```
+
 Don't forget to run `bundle update` after updating to the latest version of the gem to ensure that it is used by your Rails application.
 
 The gem also provides a helper for displaying flash messages:
 
 ```ruby