SW/assets/css/seat.css

.check_box+label{
    background:url('../../img/seat_green.png') no-repeat;
    height: 16px;
    width: 16px;
    display:inline-block;
}

.check_box:checked+label{
	background:url('../../img/seat_grey.png') no-repeat;
}

.check_box:disabled+label{
	background:url('../../img/seat_red.png') no-repeat;
}