.my-modal {
  display:none;
      position:fixed;
      z-index: 1;
      padding: 5px 0;
      left: 0;
      top: 0;
      width: 100%;
      height: 100%;
      overflow: auto;
      background-color: rgba(0,0,0,0.8);
  }
  .portrait-image {
          height: 90vh;
          margin: auto
          
          
  }
  
  .landscape-image {
          width: 65vw;
          margin: auto;
   
  }
  
  p.caption {
          color:#FFF;
          font-size: 1.3em;
  }
  .portrait-image, .landscape-image, p.caption {
  
  -webkit-animation-name: zoom;
      -webkit-animation-duration: 0.7s;
      animation-name: zoom;
      animation-duration: 0.7s;
    }
    @-webkit-keyframes zoom {
      from {-webkit-transform: scale(0)} 
      to {-webkit-transform: scale(1)}
    }
    
    @keyframes zoom {
      from {transform: scale(0.1)} 
      to {transform: scale(1)}
    }