.proxima-nova ( @size: 10, @leading: 14, @weight: 400, @tracking: 0 ) {
	font-family: 'proxima-nova', verdana, sans-serif;
	.font-size(@size);
	.leading(@leading);
	font-weight: @weight; 
	letter-spacing: @tracking;
}

	// font: 400 normal 10px/1.4rem 'promixa-nova', verdana, sans-serif;
.font-size(@sizeValue){
	@remValue: (@sizeValue / 10);
	font-size: ~"@{remValue}rem";
}
.leading(@sizeValue){
	@remValue: (@sizeValue / 10);
	line-height: ~"@{remValue}rem";
}