body {
  margin: 0;
  padding: 0;
}

h2, p {
  margin: 16px;
}

ul {
  list-style-type: none;
  margin: 0;
  padding: 1;
  overflow: hidden;
  background-color: #212121;
}

ul li {
  float: left;
}

ul li a {
  display: block;
  color: rgb(255, 255, 255);
  text-align: center; 
  padding: 19px 19px; 
  text-decoration: none;
}

ul li a:hover {
  background-color: #777777;
}