css - Minifying only a part of .LESS file -

when working .less preprocessor files, there gui tools such winless, etc. or in grunt, minify section of outputted css file?

for eg. in final .css, want main code remain neatly formatted reset code or normalize include minified.

e.g. https://github.com/tryghost/casper/blob/master/assets/css/screen.css

in file, either can minify , have min.css users use, want know if there automated option minify part of it, e.g. normalize reset section.