* {
  box-sizing: border-box;
}
img {
  width:95%);
  height:auto;
}

.col1 {
  float: left;
  width: 33%;
  text-align: center
  padding:3px;;
}

.col2{
  float: left;
  width: 34%;
  text-align: center;
  padding:3px;;
}

.col3 {
  float: left;
  width: 33%;
  text-align: center;
  padding:3px;;
}
    .thumbnail {
      border: 2px solid black;
      cursor: pointer;
    }

    #overlay {
      position: fixed;
      top: 0;
      left: 0;
      width: 100%;
      height: 100%;
      background-color: rgba(0,0,0,0.8);
      display: none;
      justify-content: center;
      align-items: center;
      z-index: 9999;
    }

    #overlay img {
      max-width: 90%;
      max-height: 90%;
    }

    #overlay:active {
      display: none;
    }
@media only screen and (max-width: 600px) {
/*For taablets */
  .col1, .col2, .col3 {
    width: 50%;
  }
@media only screen and (max-width: 480px) {
  /* For mobile phones: */
  .col1, .col2, .col3 {
    width: 100%;
  }
}

.caption {
  margin-top: 5px;
  font-size: 12px;
  color: #000;
}
.copyright {
  font-style: italic;
  font-size:10px;
}