#ball{
	position:absolute; 
	top:100px; 
	left:100px; 
	width: 40px; 
	height:40px; 
	border-radius:20px;
	background-color:blue;
}
#ballred{
	position:absolute; 
	top:100px; 
	right:100px; 
	width: 40px; 
	height:40px; 
	border-radius:20px;
	background-color:red;
}

#ballgreen{
	position:absolute; 
	width: 40px; 
	height:40px; 
	border-radius:20px;
	background-color:green;
}


#ballyellow{
	position:absolute; 
	width: 40px; 
	height:40px; 
	border-radius:20px;
	background-color:yellow;
}

body{
	background-color: lightgrey;
	margin: 0px;
}