Looks good, thanks!

@robhuzzey Since you had a little trouble understanding how to do this in Less for the first time, is there anything that could be added or improved to make contributing to Less easier for yourself or others in the future?

Thanks @matthew-dean yes, I didn't fully understand that each .less file was a test & also needed a .css file to test against.

It's really obvious to me now, but just adding a line of two in the Docs pointing that out would have really helped me out :)

I'm happy to do this if I have a little time later, although I'm not sure if it lives in here: http://lesscss.org/usage/#developing-less or here: https://github.com/less/less.js/blob/3.x/CONTRIBUTING.md