docs: add new iframe layout
diff --git a/docs/envvars.html b/docs/envvars.html
index 89f7173..49c9025 100644
--- a/docs/envvars.html
+++ b/docs/envvars.html
@@ -7,6 +7,13 @@
 </head>
 <body>
 
+<div class="header">
+  <h1>The Mesa 3D Graphics Library</h1>
+</div>
+
+<iframe src="contents.html"></iframe>
+<div class="content">
+
 <h1>Environment Variables</h1>
 
 <p>
@@ -168,5 +175,6 @@
 frequently so the source code should be consulted for details.
 </p>
 
+</div>
 </body>
 </html>