JSFiddle - React, Tailwind, and code Playground

HTML

<body>  
	<section id="top">  
		<aside id="postal_address">  
		</aside>  
	</section>  
  
	<header id="header">  
		<a href="#"><img src="http://duboatclub.files.wordpress.com/2012/08/sample.gif?w=914"></a>  
  
		<nav id="primary_nav">
			Nav tartalma
		</nav>  
	</header>
      
     Body tartalma
</body>

CSS

body {
	width:200px;
    margin:0 auto; 
    border:1px red solid;
    padding-top:300px;
}

#header {
	position:absolute; 
    top:0;
    left:0; 
    width:100%; 
    border:1px blue solid; 
    text-align:center
}