body {
        max-width: 60em;
		margin: 1em auto;
        display: flex;
        background-color: #c0c0c0;
		font-family: helvetica, tahoma, verdana, sans-serif;
		flex-flow: row wrap;
      }

img {
			max-width: 100%;
			height: auto;
	}	  
	
	/* If the screen size is 600px wide or less, set the font-size to 30px */
@media screen and (max-width: 600px) {
		font-size: 30px;
  }
      /* Mobile first - alles 100% Breite */
header, nav, nav a, article, footer {
        border-style: outset;
        padding: 10px;
        margin: 10px;
        flex: 1 100%;
      }
 
header {
        background: #f0f0f0;
        border-color: #d5d5d5;
        text-align: center;
		font-family: helvetica, tahoma, verdana, sans-serif;
		font-size: 150%;
	  }
	  
header * {
        flex: 1 1 0%;
      }
     
article {
        background: #eadbc8;
        border-color: #d5d5d5;
		font-family: helvetica, tahoma, verdana, sans-serif;	
		text-align: center;
      }
 
article {
        flex: 3 1 0%;
      }