.forme1 {
	background-color: red;
    position: absolute;
    top: 0;
    left: 0;
	width:100px;
    height: 100px;
}

.forme2 {
	background-color: blue;
    position: absolute;
    top: 0;
    right: 0;
	width:100px;
    height: 100px;
}

.forme3 {
	background-color: yellow;
    position: absolute;
    bottom: 0;
    right: 0;
	width:100px;
    height: 100px;
}

.forme4 {
	background-color: pink;
    position: absolute;
    bottom: 0;
    left: 0;
	width:100px;
    height: 100px;
}