You can add this on your css :
.products-grid .product-item,
.page-products .products-grid .product-item {
width: 48%;
margin-left: 4%;
margin-bottom: 4%;
}
@media (min-width: 768px), print {
.page-layout-2columns-left .column.main {
width: 77.16666667%;
}
.page-layout-2columns-left .sidebar-main,
.page-layout-2columns-left .sidebar-additional {
width: 22.83333333%;
}
.page-products .products-grid .product-item,
.page-products .products-grid .product-item:nth-child(4n + 1) {
width: 32%;
margin-left: 2%;
margin-bottom: 2%;
}
.page-products .products-grid .product-item:nth-child(3n+1) {
margin-left: 0;
}
#amasty-shopby-product-list .products.wrapper {
padding-left: 20px;
}
}
@media (max-width: 767px) {
.products-grid .product-item:nth-child(2n+1),
.page-products .products-grid .product-item:nth-child(2n+1) {
margin-left: 0;
}
}