ul {
  border-bottom: 1px solid #000;
  list-style: none;
  margin: 0;
  padding: 0;
  width: 100px;
}
ul li {
  position: relative;
}
ul li a {
  display: block;
  border: 1px solid #000;
  border-bottom: 1px;
  padding: 5px;
  text-decoration: none;
}
li ul {
  display: none;
  left: 99px;
  position: absolute;
  top: 0;
}
li:hover ul {
  display: block;
}



<!-- 
* html ul li {
  float: left;
}
* html ul li a {
  height: 1%;
}
-->