example.less

.centerize(@width, @height) {
	@backwards_width: (@width - @width * 2);
	@backwards_height: (@height - @height * 2);
	width: @width;
	height: @height;
	position: fixed;
	top: 50%;
	left: 50%;
	margin-top: @backwards_height / 2px;
	margin-left: @backwards_width / 2px;
}