body {
    text-align:center;
    animation: fadeIn 15s ease 0s 1 normal;
    -webkit-animation: fadeIn 15s ease 0s 1 normal;
}

@keyframes fadeIn {
    0% {opacity: 0}
    100% {opacity: 1}
}
	
@-webkit-keyframes fadeIn {
    0% {opacity: 0}
    100% {opacity: 1}
}

.pattern {
  width: 99%;
  height: 98%;
  position: absolute;
  border: 1px solid #888;
}

.pattern img {
  position: absolute;
  top: 0;
  right: 0;
  bottom: 0;
  left: 0;
  margin: auto;
}