html, body {
	width: 100%;
	height: 100%;
}

img, video {
	max-width: 100%;
    height: auto;
}

object {
	width: 100%;
    height: 600px;
}

header {
	position: fixed;
	top:0;
	left: 0;
	width:100%;
	height: 50px;

	background-color: black;
	z-index:10;
}
section {
	position: fixed;
	top: 50px;
	left: 0;
	width: 100%;
	height: 45px;
	background-color:green;
	background-image:url("https://st2.depositphotos.com/1265408/6371/i/950/depositphotos_63718961-stock-photo-vintage-abstract-background-for-design.jpg");
	z-index:10;
}
nav {
	overflow: auto;
    position: fixed;
	top: 95px;
	left: 0;
	width: 20%;
	height: calc(90% - 95px);
	background-image:url("https://st2.depositphotos.com/1265408/6361/i/950/depositphotos_63617783-stock-photo-modern-abstract-background-for-design.jpg");
	z-index:10;
}
article {
	display:inline-block;
	padding-top:95px;
	padding-bottom:10%;
	margin-left:20%;
	width: 80%;
	min-height: 100%;
	background-image:url("https://img.freepik.com/foto-gratis/fondo-playa-arena-patron-textura-espacio_1627-301.jpg?size=626&ext=jpg") ;
	background-size:100% 100%;
	z-index:10;
}

footer {
	position: fixed;
	bottom:0;
	left: 0;
	width: 100%;
	height: 10%;
	background-image:url("https://st2.depositphotos.com/1265408/6371/i/950/depositphotos_63718961-stock-photo-vintage-abstract-background-for-design.jpg");
	z-index:10;
}
.verde { color:green;
position:middle;
}