body
 {
     font-family: Arial, Helvettica, sans-serif;
     
 }
 
header
 {
     width: 80%;
     margin-left: auto;
     margin-right: auto;
     background: darkblue;
     color: white;
     overflow: hidden;
     padding: 10px;
 }

hgroup
 {
     float: left;
     width: 70%;
 }
 
 nav
 {
     float: right;
     width: 30%;
 }
 
nav a
 {
   float: right;
   text-decoration: none;
   color: white;
     
 }
 
article
 {
  width: 80%;
  margin-left: auto;
  margin-right: auto;
     
 }
 
 
footer
 {
      position: fixed;
      bottom: 0;
      left: 0;
      right: 0; 
     width: 80%;
     margin-left: auto;
     margin-right: auto;
     
     background: darkblue;
     color: white; 
     padding: 10px;
 }