rolling.html: Eliminate pointless `h2' and promote subheadings.

No idea what I was thinking back then.  Anyway, it makes rather more
sense like this.

diff --git a/rolling.html b/rolling.html
index 1feb248..dde5168 100644 (file)
--- a/rolling.html
+++ b/rolling.html
@@ -141,8 +141,6 @@
 <script type="text/javascript"><!--
        DEP_UI.add_elt_class(DEP_UI.elt('help'), 'conceal');
 --></script>
-<h2>What this program does</h2>
-
 <div id=js-note>
 <script type="text/javascript"><!--
        DEP_UI.add_elt_class(DEP_UI.elt('js-note'), 'conceal');
@@ -153,7 +151,7 @@ well.  It only requires first-party scripts;
 see <a href="#privacy">Privacy</a> for more details.
 </div>
 
-<h3>Background</h3>
+<h2>Background</h2>
 
 <p>When you pass round or square wire through flat rolls it gets flatter
 and longer, but it also gets wider.  You can exploit this to make thin
@@ -182,7 +180,7 @@ handle this case properly.
 <p>You can see the <a href="rolling-eqn.html">detailed equations</a>
 used for this calculation if you&rsquo;re interested.
 
-<h3>Use</h3>
+<h2>Use</h2>
 
 <p>Boxes with light red or white backgrounds are entry boxes for you to
 type in your requirements; boxes with dark red or grey backgrounds are
@@ -205,7 +203,7 @@ will be in millimetres; if you use inches, the results will be in
 inches.  Whatever you use, the results are displayed to only 3 decimal
 places.
 
-<h3>Code and credits</h3>
+<h2>Code and credits</h2>
 
 <p>The code which makes this page work
 is <a href="https://www.gnu.org/philosophy/free-sw.html">free
@@ -224,7 +222,7 @@ patches</a>.
 the text was written by Mark Wooding and Gary Wooding.  The data used
 to derive the computation was provided by Gary Wooding.
 
-<h3 id="privacy">Privacy</h3>
+<h2 id="privacy">Privacy</h2>
 
 <p>There are no cookies or other trackers here.  This page does not use
 externally hosted scripts, fonts, images, or anything else.  The server