diff --git a/_layouts/default.html b/_layouts/default.html
index 46f3864d..99171cc4 100644
--- a/_layouts/default.html
+++ b/_layouts/default.html
@@ -8,7 +8,7 @@
     <link rel="stylesheet" href="{{ "/assets/css/style.css?v=" | append: site.github.build_revision | relative_url }}">
     {% include head-custom.html %}
     <style>
-      header img {display:block; margin 1em auto}
+      header img {display:block; margin: 1em auto}
     </style>
   </head>
   <body>
