.section1 aside {
	float: right;
}
.section2 {
	position: relative;
}
.section2 aside {
	position: absolute;
	bottom: 0;
	right: 0;
}
.section3 aside {
	position: fixed;
	top: 0;
	right: 0;
	z-index: 1;
	background-color: green;
}
.section4 {
	position: relative;
}
#first {
	position: absolute;
	background-color: red;
	top: 50%;
	left: 50%;
	z-index: 1;
	margin-left: -150px; 
}
#second {
	background-color: black;
	position: absolute;
	top: 50%;
	left: 50%;
	margin-left: -140px;
    margin-top: 10px;
}