Absolute Mixin

_absolute.scss

@mixin absolute($top: false, $right: false, $bottom: false, $left: false) {
	position: absolute;
	@if $top != false {
		top: $top;
	}
	@if $right != false {
		right: $right;
	}
	@if $bottom != false {
		bottom: $bottom;
	}
	@if $left != false {
		left: $left;
	}
}

// Example
.item {
	@include absolute(0, 10%, false, 20%);
	// generates
	position: absolute;
	top: 0;
	right: 10%;
	left: 20%;
}