#main {
  margin-bottom: 1em;
}

#main h3 { 
  margin: 2em auto .5em;
  text-align: center;
  border-top: 3px groove #ccc;
  padding-top: 1em;
}

#main h3#categories {
  border: none;
}

ul#categories li {
  margin: .2em auto;
}

.return-to-top {
  text-align: center;
  font-weight: bold;
}

#main dt {
  margin-top: 1em;
  font-size: 120%;
}