How to Hide the "SCSS-4-WP" Admin Menu

function plt_hide_scss_4_wp_menus() {
	//Hide the "Settings → SCSS-4-WP" menu.
	remove_submenu_page('options-general.php', 'scss4wp_options');
}

add_action('admin_menu', 'plt_hide_scss_4_wp_menus', 11);

Where do I put this code?