@media screen and (min-width: 750px) and (max-width: 999px) {
  .product-grid.product-grid--grid {
    grid-template-columns: repeat(3, 1fr) !important;
  }
}

@media screen and (min-width: 1000px) {
  .product-grid.product-grid--grid {
    grid-template-columns: repeat(4, 1fr) !important;
  }
}