// Convert pixels to rems// eg. for a relational value of 12px write rem(12)// Assumes $em-base is the font-size of <html>@functionrem($pxval){@ifnotunitless($pxval){$pxval:strip-units($pxval);}$base:$em-base;@ifnotunitless($base){$base:strip-units($base);}@return($pxval/$base)*1rem;}