body {
  background-color: lightblue;
}

h1 {
  color: navy;
  margin-left: 20px;
}
html { 
   width:100%; 
   height:100%; 
   background:url(digitalstorytellers.png) center center no-repeat;
}
img {
   position: absolute;
   top: 50%;
   left: 50%;
   width: 500px;
   height: 500px;
   margin-top: -250px; /* Half the height */
   margin-left: -250px; /* Half the width */
}