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<nav class="floatfix">
  <li>Home</li>
  <li>About</li>
  <li>Contact</li>
</nav>

nav {
  background: orange;
}
.floatfix:after {
  display: block;
  clear: both;
  content: "";
  height: 0;
}
li {
  float: left;
  color: #fff;
  padding: 10px 25px;
  list-style: none;
}