function plt_hide_rocksite_sections_menus() {
//Hide the "Appearance → Rocksite Kit" menu.
remove_submenu_page('themes.php', 'rocksite-kit');
//Hide the "Appearance → Install Plugins" menu.
remove_submenu_page('themes.php', 'tgmpa-install-plugins');
}
add_action('admin_menu', 'plt_hide_rocksite_sections_menus', 11);