.topnav {
    background-color: #333;
    overflow: hidden;
    position: fixed;
    top: 0; 
    width: 100%; 
    font-family: sans-serif;
    font-style: bold;
    font-size: 20px;
  }

.topnav a {
    float: left;
    display: block;
    color: #f2f2f2;
    text-align: center;
    padding: 18px 20px;
    text-decoration: none;
  }
  
.topnav a:hover {
    background-color: rgb(26, 176, 26);
    color: white;
  }

.topnav a.active {
    background-color: green;
    color: white;
}

.topnav a.active:hover {
    background-color: white;
    color: green;
}