diff --git a/doc/browse/google-code-prettify/lang-gf.js b/doc/browse/google-code-prettify/lang-gf.js
new file mode 100644
index 000000000..2d7d8677f
--- /dev/null
+++ b/doc/browse/google-code-prettify/lang-gf.js
@@ -0,0 +1,15 @@
+/*
+  GF language
+  Customised from lang-hs.js (Haskell)
+*/
+PR.registerLangHandler(PR.createSimpleLexer([
+    ["pln", /^[\t-\r ]+/, null, "\t\n\r "],
+    ["str", /^"(?:[^\n\f\r"\\]|\\[\S\s])*(?:"|$)/, null, '"'],
+//    ["str", /^'(?:[^\n\f\r'\\]|\\[^&])'?/, null, "'"],
+    ["lit", /^(?:0o[0-7]+|0x[\da-f]+|\d+(?:\.\d+)?(?:e[+-]?\d+)?)/i, null, "0123456789"]
+], [
+    ["com", /^(?:--[^\n\f\r]*|{-(?:[^-]|-+[^}-])*-})/],
+    ["kwd", /^(?:abstract|case|cat|concrete|data|def|flags|fun|in|incomplete|instance|interface|let|lin|lincat|lindef|of|open|oper|param|pre|printname|resource|strs|table|transfer|variants|where|with)(?=[^\d'A-Za-z_]|$)/, null],
+    ["pln", /^(?:[A-Z][\w']*\.)*[A-Za-z][\w']*/],
+    ["pun", /^[^\d\t-\r "'A-Za-z]+/]
+]), ["gf"]);
diff --git a/doc/browse/google-code-prettify/prettify-own.css b/doc/browse/google-code-prettify/prettify-gf.css
similarity index 60%
rename from doc/browse/google-code-prettify/prettify-own.css
rename to doc/browse/google-code-prettify/prettify-gf.css
index 942d5b7a7..7cbf73617 100644
--- a/doc/browse/google-code-prettify/prettify-own.css
+++ b/doc/browse/google-code-prettify/prettify-gf.css
@@ -10,7 +10,7 @@
     }
   .kwd
   {
-    color:#008
+    color:#c0f
     }
   .com
   {
@@ -49,49 +49,6 @@
     color:red
     }
 }
-@media print,projection
-{
-  .str
-  {
-    color:#060
-    }
-  .kwd
-  {
-    color:#006;
-    font-weight:bold
-    }
-  .com
-  {
-    color:#600;
-    font-style:italic
-    }
-  .typ
-  {
-    color:#404;
-    font-weight:bold
-    }
-  .lit
-  {
-    color:#044
-    }
-  .pun,.opn,.clo
-  {
-    color:#440
-    }
-  .tag
-  {
-    color:#006;
-    font-weight:bold
-    }
-  .atn
-  {
-    color:#404
-    }
-  .atv
-  {
-    color:#060
-    }
-}
 pre.prettyprint
 {
   }
diff --git a/doc/browse/index.html b/doc/browse/index.html
index 7588b7d09..211a48557 100644
--- a/doc/browse/index.html
+++ b/doc/browse/index.html
@@ -8,7 +8,7 @@
   <meta name="viewport" content="width=device-width">
   <link rel="stylesheet" href="http://www.grammaticalframework.org/css/style.css">
   <link rel="stylesheet" href="style.css">
-  <link rel="stylesheet" href="google-code-prettify/prettify-own.css">
+  <link rel="stylesheet" href="google-code-prettify/prettify-gf.css">
 </head>
 <body>
   <header>
@@ -37,7 +37,7 @@
         <table id="scope_list"></table>
       </div>
       <div id="code" class="panel code">
-        <pre class="prettyprint lang-hs linenums"></pre>
+        <pre class="prettyprint lang-gf linenums"></pre>
       </div>
       <div id="help" class="panel help">
 
@@ -77,7 +77,6 @@
         <ul>
           <li>Some way of browsing just the API</li>
           <li>Better visual cues for functions in scope</li>
-          <li>Customised GF syntax highlighting (currently using a Haskell default)</li>
           <li>The page sometimes stalls when handling large files (in particular the dictionary modules)</li>
         </ul>
       </div>
@@ -85,10 +84,11 @@
     <br style="clear:both" />
   </div>
   <footer id="footer">
-  John J. Camilleri. <em>Updated 2012-05-15.</em>
+  John J. Camilleri. <em>Updated 2012-05-16.</em>
   </footer>
   <script src="http://ajax.googleapis.com/ajax/libs/jquery/1.7.2/jquery.min.js"></script>
   <script src="google-code-prettify/prettify.js"></script>
+  <script src="google-code-prettify/lang-gf.js"></script>
   <script src="script.js"></script>
 </body>
 </html>
\ No newline at end of file
