How to Hide Ghost Kit Admin Menus

function plt_hide_ghostkit_menus() {
	//Hide "Ghost Kit".
	remove_menu_page('ghostkit');
	//Hide "Ghost Kit → Blocks".
	remove_submenu_page('ghostkit', 'ghostkit');
	//Hide "Ghost Kit → Icons".
	remove_submenu_page('ghostkit', 'admin.php?page=ghostkit&sub_page=icons');
	//Hide "Ghost Kit → Typography".
	remove_submenu_page('ghostkit', 'admin.php?page=ghostkit&sub_page=typography');
	//Hide "Ghost Kit → Fonts".
	remove_submenu_page('ghostkit', 'admin.php?page=ghostkit&sub_page=fonts');
	//Hide "Ghost Kit → Breakpoints".
	remove_submenu_page('ghostkit', 'admin.php?page=ghostkit&sub_page=breakpoints');
	//Hide "Ghost Kit → CSS  JavaScript".
	remove_submenu_page('ghostkit', 'admin.php?page=ghostkit&sub_page=css_js');
	//Hide "Ghost Kit → Go Pro".
	remove_submenu_page('ghostkit', 'ghostkit_go_pro');
}

add_action('admin_menu', 'plt_hide_ghostkit_menus', 11);

Where do I put this code?