diff --git a/install-usercss.html b/install-usercss.html
index 73c5cf79..3b73d9a3 100644
--- a/install-usercss.html
+++ b/install-usercss.html
@@ -1,5 +1,5 @@
 <!DOCTYPE html>
-<html lang="en">
+<html id="stylus" lang="en">
 <head>
   <meta charset="UTF-8">
   <meta name="viewport" content="width=device-width, initial-scale=1.0">
@@ -49,7 +49,7 @@
   <script src="/edit/codemirror-default.js"></script>
   <link rel="stylesheet" href="/edit/codemirror-default.css">
 </head>
-<body>
+<body id="stylus-install-usercss">
   <div class="container">
     <div class="header">
       <h1>
diff --git a/options.html b/options.html
index 433c81c6..2d750686 100644
--- a/options.html
+++ b/options.html
@@ -24,7 +24,7 @@
   <script src="content/apply.js"></script>
 </head>
 
-<body>
+<body id="stylus-options">
   <div id="options">
 
     <div class="block">
