.overlay {
    height: 100%;
    width: 0%;
    position: fixed;
    z-index: 200;
    top: 0;
    left: 0;
    background-color: rgb(0,0,0);
    overflow-y: scroll;
    overflow-x: scroll;
    transition: 0.5s;
}

.overlay-content {
    position: relative;
    width: 100%;
    text-align: center;
}

.overlay .closebtn {
	color: white;
    position: fixed;
    top: 20px;
    right: 45px;
    font-size: 60px;
    z-index: 201;
}

.overlay .fullimg {
	max-width: 100vw; 
	height: auto;
}

.overlay .caption {
	color: white;
	font-family:Arial, Helvetica, sans-serif;
	width:50vw;
	margin-left:25vw;
	font-size:20px;
	line-height:28px;
}

@media screen and (max-height: 450px) {
  .overlay {overflow-y: auto;}
  .overlay a {font-size: 20px}
  .overlay .closebtn {
    font-size: 40px;
    top: 15px;
    right: 35px;
  }
}