Css changes not recognized

I’m building a Kirby website using xampp. I’m editing (with Atom) the index.css file, but the changes are not being recognized. When I view the code - F12 - I see the css without the changes.
Any ideas why this is happening?

It’s probably stuck in the cache, you need to hard reload the page. Usually holding the shift key and hitting reload will update. However this can get tedious… using something like browsersync is recommended as it will load the file for you in the browser when you change the css file.

The easiest way to use browsersync is through CodeKit (easiest) or Laraval Mix (little harder).