Add this to your functions.php
// Allow editors to see Appearance menu
$role_object = get_role( 'editor' );
$role_object->add_cap( 'edit_theme_options' );
function hide_menu() {
// Hide theme selection page
remove_submenu_page( 'themes.php', 'themes.php' );
// Hide widgets page
remove_submenu_page( 'themes.php', 'widgets.php' );
// Hide customize page
global $submenu;
unset($submenu['themes.php'][6]);
}
add_action('admin_head', 'hide_menu');