custom order status edit colour

Hi,

For my Woocommerce I made a plugin that adds an extra order status.
This works just fine.
But I also tried to give the new status a nice colour. But this does not work.
Can anyone help me out with the colour?

function wpblog_wc_register_post_statuses() {
	register_post_status( 'wc-shipping-progress', array(
		'label' => _x( 'In productie', 'WooCommerce Order status', 'text_domain' ),
		'public' => true,
		'exclude_from_search' => false,
		'show_in_admin_all_list' => true,
		'show_in_admin_status_list' => true,
		'label_count' => _n_noop( 'Approved (%s)', 'Approved (%s)', 'text_domain' )
) );
}

add_filter( 'init', 'wpblog_wc_register_post_statuses' );

function wpblog_wc_add_order_statuses( $order_statuses ) {
	$order_statuses['wc-shipping-progress'] = _x( 'In productie', 'WooCommerce Order status', 'text_domain' );
return $order_statuses;
}

add_filter( 'wc_order_statuses', 'wpblog_wc_add_order_statuses' );

add_action('admin_head', 'styling_admin_order_list' );
function styling_admin_order_list() {
global $pagenow, $post;

if( $pagenow != 'edit.php') return; // Exit
if( get_post_type($post->ID) != 'shop_order' ) return; // Exit

// HERE we set your custom status
$order_status = 'In productie'; // <==== HERE
?>
<style>
    .order-status.status-<?php echo sanitize_title( $order_status ); ?> {
        background: #d7f8a7;
        color: #0c942b;
    }
</style>
<?php
}