#gallery {
   line-height:0;
   -webkit-column-count:5; /* split it into 5 columns */
   -webkit-column-gap:5px; /* give it a 5px gap between columns */
   -moz-column-count:5;
   -moz-column-gap:5px;
   column-count:5;
   column-gap:5px;
}

#gallery img {
   width: 100% !important;
   height: auto !important;
   margin-bottom:5px; /* to match column gap */
}

@media (max-width: 1200px) {
   #gallery {
    -moz-column-count:    4;
    -webkit-column-count: 4;
    column-count:         4;
   }
}
@media (max-width: 1000px) {
   #gallery {
    -moz-column-count:    3;
    -webkit-column-count: 3;
    column-count:         3;
   }
}
@media (max-width: 800px) {
   #gallery {
    -moz-column-count:    2;
    -webkit-column-count: 2;
    column-count:         2;
   }
}
@media (max-width: 400px) {
   #gallery {
    -moz-column-count:    1;
    -webkit-column-count: 1;
    column-count:         1;
   }
}

#gallery .image-container {
   position: relative;
}

.image-overlay {
   position: absolute;
   bottom: 0;
   left: 0;
   width: 100%;
   background-color: rgba(0, 0, 0, 0.7); /* You can adjust the opacity and color */
   color: white;
   padding: 15px;
   display: none;
   margin-bottom: 5px;
}

.image-container:hover .image-overlay {
   display: block;
}