#loading-overlay {
  position: fixed;
  left: 0;
  right: 0;
  top: 0;
  bottom: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.4);
  border-radius: 5px;
  display: none;
  
  #loading-content {
    position: absolute;
    margin: auto;
    left: 50%;
    top: 50%;
    transform: translate(-50%, -50%);
  }
}