body 
{
margin: 0;
padding: 0;
font: 85% arial, hevetica, sans-serif;
text-align: center;
color: #505367;
background-color: #000000;
}
	
#zentriert {
  position:absolute;
  top:50%;
  left:50%;
  width:30em;
  height:20em;
  margin-left:-15em;
  margin-top:-13em;
}