#preview {
  position: absolute;
  border: 1px solid #ccc;
  padding: 0;
  display: none;
  color: #fff;
}
#preview img.blank {
  width: 100%;
  height: 100%;
  display: block;
  position: absolute;
  left: 0;
  top: 0;
  z-index: 1;
}