diff --git a/www/slide/slide.js b/www/slide/slide.js
index 87d9405a2..c7df80d77 100644
--- a/www/slide/slide.js
+++ b/www/slide/slide.js
@@ -69,6 +69,12 @@ define([
         $content.find('.slide-container').first().css('margin-left', -(i*100)+'%');
         updateFontSize();
         change(Slide.lastIndex, Slide.index);
+        $modal.find('#button_left > span').css({
+            opacity: Slide.index === 0? 0: 1
+        });
+        $modal.find('#button_right > span').css({
+            opacity: Slide.index === (getNumberOfSlides() -1)? 0: 1
+        });
     };
     var draw = Slide.draw =  function (i) {
         if (typeof(Slide.content) !== 'string') { return; }