body { margin: 0.5em ;}

ul {
  list-style: none;
  margin-left: 0;
  padding-left: 0;
  font-weight: bold
}
li a {
  text-decoration: none;
  display: block;
  padding: 0.2em;
  width: 12em;
  border-bottom: 1px solid #fff;
  color: #fff;
  background: #36c;
}
li a:hover {
  color: #fff;
  background: #9cc;
}