#bloc1 {
	width: 400px;
	background-color: lightcyan;
	position: relative;
}

#bloc2 {
	display: inline-block;
	width: 100px;
	height: 100px;
	background-color: rgba(255,0,0,0.4);
	position: absolute;
	top: 15px;
	left: 15px;
}

#bloc3 {
	display: inline-block;
	width: 80px;
	height: 120px;
	background-color: rgba(100,200,0,0.4);
	position: absolute;
	top: 15px;
	right: 15px;
}