#preload {
    display: none;
    position: fixed; /* Sit on top of the page content */
    width: 100%; /* Full width (cover the whole page) */
    height: 100%; /* Full height (cover the whole page) */
    top: 0; 
    left: 0;
    right: 0;
    bottom: 0;
    background-color: rgba(0,0,0,0.5); /* Black background with opacity */
    z-index: 100; /* Specify a stack order in case you're using a different order for other elements */
  }
.overlay-content{
    position: absolute;
    left: 50%;
    margin-left: -100px;
    top:30%;
}