.floor {
	background-color: lightgray;
	border: solid 1px black;
	position: relative;
	width: 640px;
	height: 480px;
	overflow: hidden;
}

.place {
	background-color: white;
	position: absolute;
	border: solid 1px black;
	z-index: 2;
}

.ui-draggable-dragging {
	z-index: 3;
}