gallery-item.scss

.gallery .item {
   // Small screen is set to 2 column grid
   @include media($small-screen) {
     @include span-columns(2);
     @include omega(1n);
   }
   // Medium screen is set to a 4 column grid
   @include media($medium-screen) {
     @include span-columns(2);
     @include omega(2n);
   }
   // Large screen is set to a 8 column grid
   @include media($large-screen) {
     @include span-columns(2);
     @include omega(4n);
   }
   // XL screen is set to a 12 column grid
   @include media($xl-screen) {
     @include span-columns(3);
     @include omega(4n);
   }
}