Font tweaks

Apply Roboto to <article><section> and not just <p>. Non-<p> tags inside
of articles weren't getting it, like <ul>.

Shrink code font size from 90% to 80%. This at least keeps code that
stays within 80 char lines looking nice.

media/css/index.css

@@ -4,12 +4,13 @@ body {
   font-family: 'Quicksand', sans-serif;
 }
 
-p {
+article section {
   font-family: 'Roboto', sans-serif;
 }
 
 pre code {
   font-family: 'Source Code Pro', monospace;
+  font-size: 80%;
 }
 
 a {