diff --git a/case-study-porting-chardet-to-python-3.html b/case-study-porting-chardet-to-python-3.html
index 1c0a3aa..5c4788f 100644
--- a/case-study-porting-chardet-to-python-3.html
+++ b/case-study-porting-chardet-to-python-3.html
@@ -8,12 +8,14 @@
 <body>
 <h1>Case study: porting chardet to Python 3</h1>
 
-<ul class="toc">
+<ol class="toc">
 <li><a href="#running2to3">Running <code class="filename">2to3</code></a></li>
 <li><a href="#falseisinvalidsyntax"><code>False</code> is invalid syntax</a></li>
+<li><a href="#nomodulenamedconstants">No module named <code class="filename">constants</code></a></li>
 <li><a href="#namefileisnotdefined">Name '<var>file</var>' is not defined</a></li>
+<li><a href="#cantuseastringpattern">Can't use a string pattern on a bytes-like object</a></li>
 <li><a href="#cantconvertbytesobject">Can't convert '<code>bytes</code>' object to <code>str</code> implicitly</a></li>
-</ul>
+</ol>
 
 <section id="running2to3">
 
diff --git a/dip3.css b/dip3.css
index 6fcb32c..907be62 100644
--- a/dip3.css
+++ b/dip3.css
@@ -27,3 +27,5 @@ figure{display:block;text-align:center;margin:1.75em 0}
 figure img{display:block;margin:0 auto}
 section,article,footer{display:block}
 var{font-family:monospace;font-style:normal}
+body{counter-reset:h2}
+h2:before{counter-increment:h2;content:counter(h2) ". "}
