diff --git a/src/vector/index.html b/src/vector/index.html
index 1a242a80ed..29b1f13221 100644
--- a/src/vector/index.html
+++ b/src/vector/index.html
@@ -43,7 +43,7 @@
         if (match) {
             var title = match[1].charAt(0).toUpperCase() + match[1].slice(1);
         %>
-           <link rel="stylesheet" disabled="disabled" title="<%= title %>" href="<%= file %>">
+           <link rel="stylesheet" disabled="disabled" data-mx-theme="<%= title %>" title="<%= title %>" href="<%= file %>">
         <% } else { %>
            <link rel="stylesheet" href="<%= file %>">
         <% }