We've added some example CSS below if you want to use it for testing.
This tool is designed to bring down the size of CSS files, and while this will help, it can't make decisions like what your file includes and where it should be within your site.
Current indications point to between 15% and 25% average reductions on size dependent on code styling, but as you can see in the example it has achieved 44%.
We've been using this for a number of years internally, so have confidence in it, however if you find it breaks your code then please feel free to contact us.