#image-preview {
  width: 400px;
  height: 400px;
  position: relative;
  overflow: hidden;
  background-color: #ffffff;
  color: #ecf0f1;
}
#image-preview input {
  line-height: 200px;
  font-size: 200px;
  position: absolute;
  opacity: 0;
  z-index: 10;
}
#image-preview label {
  position: absolute;
  z-index: 5;
  opacity: 0.8;
  cursor: pointer;
  background-color: #bdc3c7;
  width: 200px;
  height: 50px;
  font-size: 20px;
  line-height: 50px;
  text-transform: uppercase;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  margin: auto;
  text-align: center;
}