diff --git a/demo.html b/demo.html
index 8ebb663..633b23a 100644
--- a/demo.html
+++ b/demo.html
@@ -2,6 +2,7 @@
 <html lang="en">
 <head>
 	<meta charset="utf-8"/>
+	<meta name="viewport" content="width=device-width, initial-scale=1.0">
 	<link rel="stylesheet" href="css/halfstyle.css"/>
 	<script type="text/javascript" src="js/jquery.min.js"></script>
 	<script type="text/javascript" src="js/halfstyle.js" ></script>
