body {margin:0;}

.topnav {
  overflow: hidden;
  background-color: #333;
}

.topnav a {
  float: left;
  display: block;
  color: white;
  text-align: center;
  padding: 12px 12px;
  text-decoration: none;
  font-size: 17px;
}

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

.topnav .menu {
  display: none;
}

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

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

.hidden {
  display: none;
}

@media screen and (max-width: 600px) {

  .topnav {
    position: sticky;
    top: 0;
    }

  .topnav a:not(:first-child) {display: none;}

  .topnav a.menu {
    position: absolute;
    right: 0;
    top: 5px;
    display: block;
  }

  .topnav.responsive {position: relative;}

  .topnav.responsive .menu {
    position: absolute;
    right: 0;
    top: 5px;
  }

  .topnav.responsive a {
    float: none;
    display: block;
    text-align: left;
  }

  .topnav.responsive h1 {
    display: none;
  }

  .hidden {
    display: block;
    color: white;
    text-decoration: none;
    font-size: 17px;
    text-size-adjust: auto;
    text-align: left;
  }

  .logo {
    width: 50px;
  }

}