Get the nethack page looking good again

Update all the CSS classes and fix the layout so it looks good in the new theme.
Convert a bunch of CSS classes to BEM style.

layouts/shortcodes/nethack/best_game.html

@@ -3,7 +3,7 @@
 {{ range $nethack_data }}
   {{ $logfile = $logfile | append .logfile }}
 {{ end }}
-<ol class="logfile">
+<ol class="nethack-logfile">
   <li>
     {{ partial "nethack/logentry.html" (index (sort $logfile "score" "desc") 0) }}
   </li>