* {
	padding: 0;
	margin: 0;
}

html, body {
	min-height: 100%;
}

body {
	background-image: url(Gluehlampe_explodiert.jpg);
	background-position: top center;
	background-size:  auto 100%;
	font-family: sans-serif;
}

.header {
	min-height: 80px;
	background-color: rgba(0,0,0,0.5);
}

.header h1 {
	color: white;
	height: 80px;
	line-height: 80px;
	margin-left: 30px;
	font-size: 45px;
}

.header ul {
	overflow: hidden;
}

.header ul li {
	list-style-type: none;
	float: left;
	margin: 5px;
}

.header ul li a {
	font-size: 19px;
	font-weight: bold;
	border: 1px solid #808080;
	color: #808080;
	display: block;
	padding: 5px;
	text-decoration: none;
}

.header ul li a:hover {
	color: white;
	border-color: white;
}

.main {
	background-color: rgba(0,0,0,0.5);
	color: white;
	padding: 25px;
	margin-top: 50px;
}