fixed issue per ticket

Author: gjohnson

content/custom-events/ch11-custom-events.html

@@ -116,7 +116,7 @@ <h2 class="title">
         $(this).removeClass('off').addClass('on');
     })
     .bind('turnOff', function(e) {
-        $(this).removeClass('off').addClass('on');
+        $(this).removeClass('on').addClass('off');
     });
 
 $('.switch, .clapper').click(function() {