body { margin:0;}
.claseprincipal{
	background: linear-gradient(to bottom right, #00e6ff, #3a00ff);
	height: 100vh;
    width: 100vw;
	margin: 0px auto;
	padding: 0px;
}
.imagencentrada{
	position: absolute;
    left: 50%;
    top: 50%;
    transform: translate(-50%, -50%);
    -webkit-transform: translate(-50%, -50%);
}