Can't compile LESS because of relative paths in Mix

I have some html template bought on themeforest. I have LESS files in it, so I want that compiled without unnecessary code, and sized down. However I can't compile it because of bunch of problems with paths.

First problem was with importing google fonts like this: @import url('https://fonts.googleapis.com/css?family=Roboto:400,300,500,700');

But I found some discussion on the Internet about webpack, and adding .css on the url solve that.

However I have some LESS file that imports some font file. Withing the file there is relative path '../fonts/...' to the font which does exist, however it throws error: Error: Can't resolve './icons/fonts/themify.eot'

Do you have any suggestion or there is some catch I missed with webpack when compiling LESS? :) Just to say I don't want to disable processing CSS paths because I wanted referenced fonts etc, distributed to public folder.