Fixes #9 - Update cross-promotional section

static/css/main.css

 *
 {
   font-family: Arial, sans;

[ire, 2018/02/06 16:31:14]

The correct font-family isn't being applied yet so the implementation may not
look exactly correct. I'm not sure why the font wasn't changed with the start of
the updated design, I'll double check about that and handle it in a separate
issue.

   font-size: 16px;
 }
 
 body
 {
   margin: 0;
   line-height: 1.5;
 }
 
 #content
@@ skipping 29 matching lines @@
 }
 
 .sprite
 {
   display: inline-block;
   font-size: 0px; /* fix for IE6 height bug */
   background-image: url(../img/sprite-main.png);
   background-repeat: no-repeat;
 }
 
-#adblock-browser-notification
-{
-  text-align: center;
-}
-
-#adblock-browser-notification a
-{
-  font-weight: bold;
-}
-
-#adblock-browser-notification img
-{
-  vertical-align: bottom;
-  width: 25px;
-  height: 25px;
-}
-
-#adblock-browser-notification span
-{
-  white-space: nowrap;
-  margin-left: 1em;
-}
-
-[dir="rtl"] #adblock-browser-notification span
-{
-  margin-left: 0;
-  margin-right: 1em;
-}
-
 .toc
 {
   display: inline-block;
   border: 1px solid #aaa;
   background: #fff;
   padding: 16px 20px;
 }
 
 .toc ul
 {
@@ skipping 84 matching lines @@
 .content h2,
 .content h3,
 .content h4,
 .content h5
 {
   font-weight: bold;
   margin: 32px 0 16px 0;
   margin: 2rem 0 1rem 0;
 }
 
-.content h1 { font-size: 1.8em; }
+.content h1,
+.content .h1 { font-size: 1.8em; }
+
 .content h2 { font-size: 1.4em; }
 .content h3 { font-size: 1.3em; }
 .content h4 { font-size: 1.2em; }
 .content h5 { font-size: 1.1em; }
 
 @media(min-width: 768px)
 {
   .content h1 { font-size: 2.4em; }
   .content h2 { font-size: 1.6em; }
 }
@@ skipping 512 matching lines @@
   {
     display: none;
   }
 
   /* overriding display:none above */
   #footer #social-list
   {
     display: block;
   }
 }