body {
	font-family: Arial;
	margin: 0;
}
.container {
	display: flex;
	justify-content: center;
}
.content {
	max-width: 83ch;
	background-color: lightblue;	
}

.side-left {
	width: 1em;
	background-image: linear-gradient(to right, white, lightblue);
}
.side-right {
	width: 1em;
	background-image: linear-gradient(to left, white, lightblue);
}
@media screen and (orientation: portrait) {
	.side-left, .side-right {
		display: none;
	}		
	.content {
		max-width: 100%;
		width: 100%;
	}
}

nav,
section,
footer {	
	padding-left: 1em;
	padding-right: 1em;
}

section,
footer {
	padding-top: 1em;
	padding-bottom: 1em;
}
nav,
article {
	padding-bottom: 1em;
}

hr {
	border-top: 2px solid black;
	margin: 0 1em 0 1em;
}