/* Add a black background color to the top navigation */
nav {
    display: block;
  background-color: #333;
  position: relative;
  z-index: 10; 
}

/* Style the links inside the navigation bar */
nav a {
  float: left;
  color: #f2f2f2;
  text-align: center;
  padding: 14px 16px;
  text-decoration: none;
  font-size: 17px;
}

/* Change the color of links on hover */
nav a:hover {
  background-color: #ddd;
  color: black;
}

/* Add a color to the active/current link */
nav a.active {
  background-color: #4CAF50;
  color: white;
}