article, aside, footer, header, main, nav, section {
	display: block;
}

html, body, h1, h2, h3, h4, h5, h6, ul, li, a, p, article, aside, footer, header, main, nav, section {
	padding: 0;
	margin: 0;
}

body {
	background-color: gray;
}

nav li {
	display: inline;
	margin-left: 15px;
	margin-right: 15px;
}

nav {
	padding: 5px;
	margin-top: 1px;
	background-color: #0000ff;
}

li a {
	text-align:center;
	color: white;
}

.banner {
	background-color: #000080;
	padding: 10px 20px;
	text-align: center;
	color: white;
}

body {
	width: 960px;
	margin-left: auto;
	margin-right: auto;
}

header img {
	float: left;
}

footer {
  clear: both;
  background-color: #20416c;
  color: white;
  padding: 5px 20px;
}

footer  a{
  clear: both;
  background-color: #20416c;
  color: white;
}

iframe{
	margin-bottom: 10px;
	margin-top: 10px;
}