<div class="modal">
            <div class="modal-Content">
            <h1>Cool Images</h1>
            <img src="https://picsum.photos/400/400" alt="">

            </div>
        </div>

*, 
*:before, 
*:after { 
    -webkit-box-sizing: border-box;
    -moz-box-sizing: border-box; 
    box-sizing: border-box;
 }
.modal
{
    position: fixed;
    top: 0;
    bottom: 0;
    left: 0;
    display: block;
    width: 100%;
    height: 100%;
    background-color: rgba(3, 59, 117, .5);
}
.modal-Content
{
    position: fixed;
    top: 50%;
    left: 50%;
    display: block;
    padding: 20px;
    transform: translate(-50%, -50%);
    border-radius: 5px;
    background-color: #fff;
    -webkit-box-shadow: 0 9px 13px -2px rgba(50, 50, 50, .52);
       -moz-box-shadow: 0 9px 13px -2px rgba(50, 50, 50, .52);
            box-shadow: 0 9px 13px -2px rgba(50, 50, 50, .52);
           text-align: center;
}
	


  .modal-Content h1{
    margin: 0 0 20px 0;
  }