@media screen and (max-width: 1199px) {
.boxDiv {
    right: 0;
	top:0;
	left: auto;
	background-color:green;
}
}
@media screen and (max-width: 991px) {
.boxDiv {
    left: 0;
	bottom:0;
    top: auto;
	background-color:red;
	border:2px solid green;
}
}
@media screen and (max-width: 767px) {
.boxDiv {
    right: 0;
	bottom:0;
	left:auto;
	background-color:yellow;
}
}