html {
	background: #f8f8f8f8;
	font-family: sans-serif;
}

body {
	max-width: 800px;
	margin: 0 auto;
	padding-bottom: 2rem;
}

h1 + h2 {
	margin-top: -1rem;
}

nav {
	text-align: center;
	margin-bottom: 1rem;
}

nav ul {
	list-style: none;
	padding-left: 0;
	margin: 1rem 0;
}

nav ul li {
	display: inline;
}

nav ul li:not(:first-child) {
	display: inline;
	padding-left: 1rem;
}

article {
	max-width: 800px;
	margin: 0 auto;
}

img {
	display: block;
	max-width: 80%;
	margin: 1rem auto;
}

.command {
	color: #22c;
}

.center {
	text-align: center;
}

.alert {
  padding: 0.5rem;
  margin: 0 -0.5rem;
  border: 1px solid #f5c6cb;
  margin-bottom: 1rem;
  background: #f8d7da;
  color: #721c24;
}

video {
	display: block;
	margin: 1rem auto;
	max-width: 80%;
}