#main_nav {
  background: #1A1A1A;
  text-align: center;
  padding: 4px 0;
  font-size: 1.1em;
}
#main_nav ul {
  margin: 0;
  padding: 0;
}
#main_nav li {
  display: inline;
  margin: 0 6px;
}
#main_nav a {
  color: #CCC;
  text-decoration: none;
}
#main_nav a img {
  vertical-align: middle;
}
#main_nav a:hover {
  color: #EEE;
  text-decoration: none;
}
#main_nav .on a {
  color: #FFF;
}

#improve {
  margin-right: 5px;
  margin-bottom: 15px;
  font-weight: bold;
  font-size: 0.8em;
  float: right;
}