diff --git a/js/ditto.js b/js/ditto.js
index db65c19..5009e87 100644
--- a/js/ditto.js
+++ b/js/ditto.js
@@ -39,6 +39,16 @@ function initialize() {
     // page router
     router();
     $(window).on('hashchange', router);
+	$(document).on('scroll', function (evt) {
+			var newScroll = $(document).scrollTop(),
+		    diff = newScroll-lastScroll;
+			treshold = (treshold+diff>headerHeight) ? headerHeight : treshold+diff;
+			treshold = (treshold < 0) ? 0 : treshold;
+    
+			header.css('bottom', (-treshold)+'px');
+
+			lastScroll = newScroll;
+	});	
 }
 
 function init_sidebar_section() {