body {
  margin: 0;
  padding: 50px 0 0 0;
}

.navigation {
  position: fixed;
  top: 0;
  width: 100%;
  text-align:center;
  height: 50px;
  line-height:50px;
  transition: top .2s ease-in-out;
  background: #3498DB;
  border-bottom:3px solid #2980B9;
  color: white;
}

.is-hidden { top: -53px; }

.is-visible { }