body {
  background: #333;
  font: 12px/2 Arial, sans-serif;
  text-align: center;
}

a {
  color: #fff;
}

#paper {
  background: #fff;
  margin: -200px 0 0 -300px;
  width: 600px;
  height: 400px;
  position: absolute;
  top: 50%;
  left: 50%;
  bottom: auto;
  right: auto;
}