.gallery {
  background: #EEE;
}

.gallery-cell {
  width: 25%;
  height: 200px;
  margin-right: 10px;
  
  counter-increment: gallery-cell;
}

/* cell number */
.gallery-cell:before {
  display: block;
  text-align: center;
  
  line-height: 200px;
  font-size: 80px;
  color: white;
}

/* Tablet */
@media (max-width: 992px) {
  .gallery-cell {
    width: 40%;
    height: 190px;
  }
}

/* Mobile */
@media (max-width: 576px) {
  .gallery-cell {
    width: 85%;
    height: 180px;
    margin-right: 12px;
  }
}