I recently came across LiveReload and was impressed. Actually impressed is an under statement. I was amazed. LiveReload has really improved the way I work with css. As it says on its github page LiveReload is browser extension & a command-line tool that:

  1. Applies CSS and JavaScript file changes without reloading a page.
  2. Automatically reloads a page when any other file changes (html, image, server-side script, etc).