html { height:100%;}
body {
    background-color: #000;
    font-size: 100%;
    margin: 0;
    padding: 0;
    text-align:center; 
    height:100%;
}


.center img {
  position: absolute;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%);
  width: 30%;
  height: 50%;
}