.columns-4 {
  -webkit-column-count: 1;
  -moz-column-count: 1;
  column-count: 1;
}

@media (min-width: 575px) {
  .columns-4 {
    -webkit-column-count: 2;
    -moz-column-count: 2;
    column-count: 2;
  }
}

@media (min-width: 991px) {
  .columns-4 {
    -webkit-column-count: 4;
    -moz-column-count: 4;
    column-count: 4;
  }
}