etc/isabelle.css

   line-height: 120%;
 }
 
 .theories { background-color: #FFFFFF; padding: 10px; }
 .sessions { background-color: #FFFFFF; padding: 10px; }
+
+.sessions pre { margin: 0px; }
 
 .name     { font-style: italic; }
 .filename { font-family: fixed; }