.pic {
  width: 220px;
  height:220px;
  
  cursor: -moz-zoom-in; 
    cursor: -webkit-zoom-in; 
    cursor: zoom-in;
}
.fs {
    width: auto;
    height:100vh;
    max-width:100vh;
    max-height:100vh;
    cursor: -moz-zoom-out; 
    cursor: -webkit-zoom-out; 
    cursor: zoom-out;
}
.fsw {
    width: 100vw;
    height:auto;
    max-width:100vw;
    max-height:100vh;    
    cursor: -moz-zoom-out; 
    cursor: -webkit-zoom-out; 
    cursor: zoom-out;
}
#overlay {
  position: fixed;
  display: none;
  width: 100%;
  height: 100%;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: rgba(0,0,0,0.5);
  z-index: 2;
  cursor: pointer;
margin:auto auto;