diff --git a/html/js/jquery.unveil.js b/html/js/jquery.unveil.js
index b42ebdb..fa096c4 100644
--- a/html/js/jquery.unveil.js
+++ b/html/js/jquery.unveil.js
@@ -28,7 +28,7 @@
                     var flag = false;
                     for (var item in blackList) {
                         var u = blackList[item];
-                        if (source.indexOf(u)) {
+                        if (source.indexOf(u) !== -1) {
                                 flag = true;
                             }
                         }