[Theme: Storefront] Cart placement and removing primary navigation

Thanks to many posts on this forum I succeeded in placing my menu next to my logo on my website: http://www.yvsdesign.nl

Next I want to remove the primary navigation bar, because it takes up a lot of space. At this forum I came across some useful code to insert in my function.php folder:

add_action( 'init', 'jk_remove_storefront_primary_nav' );
function jk_remove_storefront_primary_nav() {
remove_action( 'storefront_header', 'storefront_primary_navigation', 50 );
}

But when I copy this to my function.php folder, my whole site goes blank.

When I try to remove the primary navigation through code in the style.css folder:

@media only screen and (min-width: 768px) {
.storefront-primary-navigation { display: none !important; }
}

it works, but then my shoppig cart disappears.

Can someone help me to remove the primary navigation, but keep the shopping cart?

Thanks in advance!

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