Add CLASS to admin body if user is not an Administrator

admin.php

<?php
//Add class to admin body if user is not an Administrator
	if( ! current_user_can('administrator') ) {
		add_filter( 'admin_body_class', 'rw_admin_only_body_class' );
		function rw_admin_only_body_class( $classes )
		{
			$classes = 'admin-readonly';
			return $classes;
		}
	}

/* 
* This function can be particularly useful when you don't other users except Administrator to make changes to given fields 
* ie make those fields "read-only" or "hidden" for other users
*/
?>