nav ul {
  list-style-type: none;
  margin: 0;
  padding: 0;
  overflow: hidden;
  background-color: #333333;
  position: fixed;
  top: 0;
  width: 100%;
}

nav ul li {
  float: left;
}

nav ul li a {
  display: block;
  color: white;
  text-align: center;
  padding: 14px 16px;
  text-decoration: none;
}

nav ul li a:hover {
  background-color: #111111;
}

nav ul li a.active {
  background-color: #04AA6D;
}

@media screen and (max-width: 600px) {
  body {
    padding-top: 0;
  }
  nav ul {
    position: static;
    width: 100%;
  }
  nav ul li {float: none;}
}