You can find the code for this popup in js/functions.js
file. Remove the following lines
var html = [
'<div class="added-to-cart">',
'<p>' + basel_settings.added_to_cart + '</p>',
'<a href="#" class="btn btn-style-link close-popup">' + basel_settings.continue_shopping + '</a>',
'<a href="' + basel_settings.cart_url + '" class="btn btn-color-primary view-cart">' + basel_settings.view_cart + '</a>',
'</div>',
].join("");
$.magnificPopup.open({
items: {
src: '<div class="white-popup add-to-cart-popup popup-added_to_cart">' + html + '</div>',
type: 'inline'
}
});
$('.white-popup').on('click', '.close-popup', function(e) {
e.preventDefault();
$.magnificPopup.close();
});
But take into account that our theme has minified versions of the script and you need to disable this option in Theme Settings -> Performance to see the result.