div.n-textarea {
	position: relative;
}

.generate-textarea-lines(@n, @i: 2) when (@i =< @n) {
	textarea.l@{i}, textarea.form-control.l@{i} {
		height: (@i * @form-control-height);
	}
	.generate-textarea-lines(@n, (@i + 1));
}

.generate-textarea-lines(10);