2 column grid on all screens

Try to add the following code snippet instead of previous one:

.basel-products-holder {
	display: -webkit-box;
	display: -ms-flexbox;
	display: flex;
	-ms-flex-wrap: wrap;
	flex-wrap: wrap;
	-webkit-box-orient: horizontal;
	-webkit-box-direction: normal;
	-ms-flex-direction: row;
	flex-direction: row;
	-webkit-box-pack: start;
	-ms-flex-pack: start;
	justify-content: flex-start;
}

.basel-products-holder:after, 
.basel-products-holder:before{
  display: none;
}

.product-grid-item.col-xs-12 {
	width: 50%;
	max-width: 50%;
	-ms-flex-preferred-size: 50%;	
	flex-basis: 50%;
}

.basel-products-holder > .clearfix {
	display: none !important;
}

Regards