diff --git a/sample-client.html b/sample-client.html
index d3f10c8..6ed8d39 100644
--- a/sample-client.html
+++ b/sample-client.html
@@ -1,19 +1,19 @@
 <html>
   <head>
     <title>Coce Client Sample</title>
-    <script src="//ajax.googleapis.com/ajax/libs/jquery/1.9.0/jquery.min.js"></script>
+    <script src="https://ajax.googleapis.com/ajax/libs/jquery/1.9.0/jquery.min.js"></script>
     <script src="coceclient.js"></script>
     <script>
     $(document).ready(function(){
-       var ids = [];
+       const ids = [];
        $("[id^=coce-thumbnail]").each(function(i) {
          ids.push($(this).attr("class"));
        });
        if (ids.length == 0) return;
-       var coceClient = new CoceClient('http://localhost:8080', 'ol,gb,aws');
+       const coceClient = new CoceClient('http://localhost:8080', 'ol,gb,aws');
        coceClient.fetch(ids, function(id, url) {
          $("[id^=coce-thumbnail]."+id).each(function() {
-           var img = document.createElement("img");
+           const img = document.createElement("img");
            img.src = url;
            img.title = url;
            $(this).append(img); 
