Assets on production mode

Zamień:

# Disable Rails's static asset server (Apache or nginx will already do this)
  config.serve_static_assets = false

Na:

# Disable Rails's static asset server (Apache or nginx will already do this)
  config.serve_static_assets = true

rake assets:clean
sudo /etc/init.d/nginx restart 

Jeśli nie działa, to:

rake assets:precompile
sudo /etc/init.d/nginx restart