#navbar {
  background-color:#000000;
  position:fixed;  
  z-index:1; /*Add this*/
  width:100%;
  height:50px;
  text-align:center;
  vertical-align:middle;
  top:0px;}
#navbar ul {
  list-style-type: none;
  margin: 0;
  padding: 0;
  overflow: hidden;
  background-color: #333;
}

#navbar li {
  float: left;
  border-right:1px solid #bbb;
}

#navbar li:last-child {
  border-right: none;
}

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

#navbar li a:hover:not(.active) {
  background-color: #111;
}

#navbar .active {
  background-color: #4CAF50;
}