diff --git a/templates/partial/header.html.ep b/templates/partial/header.html.ep
index 850e77b..2422819 100644
--- a/templates/partial/header.html.ep
+++ b/templates/partial/header.html.ep
@@ -3,5 +3,5 @@
 %= asset 'korap.css'
 %= asset 'korap.js'
   <meta charset="utf-8" />
-  <meta name="viewport" content="width=device-width;initial-scale=1.0;" />
+  <meta name="viewport" content="width=device-width, initial-scale=1.0, maximum-scale=1.0, minimum-scale=1.0, user-scalable=false, user-scalable=no" />
 </head>