body 
{ 
	background-color: grey;
	font-size: 1em;

}

@media screen and (max-width:960px){
body { background-color: red;
		font-size: 1em;

}
}

@media screen and (max-width:768px){
body { background-color: orange;
		font-size: 1em;
}

}

@media screen and (max-width:550px){
body { background-color: yellow;
		font-size: 1em;
}
}

@media screen and (max-width:420px){
body { background-color: blue;
		font-size: 2em;

}
}