CSS Folding triangle from corner of any element

triangleFold.less

.triangleFold(@size, @basebackground, @foldcolor) {
	&:after {
		content: '';
		width: 0;
		height: 0;
		border-left: @size solid transparent;
		border-right: 0px solid transparent;
		border-bottom: @size solid @basebackground;
		position: absolute;
		bottom: 0px;
		right: 0px;
	}
	&:before {
		content: '';
		width: 0;
		height: 0;
		border-top: @size solid @foldcolor;
		border-left: 0px solid transparent;
		border-right: @size solid transparent;
		position: absolute;
		bottom: 0px;
		right: 0px;
	}
}

// Use as follows:

div.trianglefold {
    .triangleFold(12px, @basebackground, @foldcolor);
}