Special column mixins and functions allowing easy generation of column layouts

_cols.scss

@function col($col-width-px, $container-width: $content-width-max) {
	@return percentage(strip-unit($col-width-px) / strip-unit($container-width));
}

@mixin col($col-width-px, $container-width: $content-width-max, $gutter-px: none, $float: left) {
	float: $float;
	display: block;
 	width: col($col-width-px, $container-width);
 	@if ($gutter-px != 'none') {
 		margin-#{if($float == 'left','right','left')}: col($gutter-px,$container-width);
 	}
}

@mixin cols($col-width-px, $container-width: $content-width-max, $float: left) {
	$cols: strip-unit(floor($container-width/$col-width-px));
	$gutter-px: ($container-width % $col-width-px) / ($cols - 1);
	float: $float;
	display: block;
 	width: col($col-width-px, $container-width);
 	margin-right: col($gutter-px,$container-width);
 	&:nth-child(#{$cols}n#{if($float == 'left','','+1')}) {
 		margin-right: 0;
 	}
}