.topnav {
  background-color: hsla(0,0%,20%,0);
  position:fixed;
  width:100%;
  top:0;
  z-index:9;
}

.topnav-centered {
  overflow: hidden;
  max-width:1050px; 
  margin:auto; 
  box-sizing: border-box;
} 
  
.topnav a {
  float: left;
  display: block;
  color: #55ff00;
  text-align: center;
  padding: 24px 16px;
  text-decoration: none;
  text-transform: uppercase;
  font-family: Calibri, Verdana, sans-serif;
  font-size: 20px;
}

.topnav .icon {
  display: none;
}

.topnav .logo {
  cursor: default;
  padding:15px 30px;
}    
.dropdown {
  float: left;
  overflow: hidden;
}
.dropdown .dropbtn {
  font-size: 20px;    
  border: none;
  outline: none;
  color: #55ff00;
  padding: 24px 16px;
  text-transform: uppercase;
  background-color: inherit;
  font-family: inherit;
  margin: 0;
}
.dropdown-content {
  display: none;
  position: fixed;
  background-color: #f9f9f9;
  min-width: 160px;
  box-shadow: 0px 8px 16px 0px rgba(0,0,0,0.2);
  z-index: 1;
}
.dropdown-content a {
  float: none;
  color: black;
  font-size:20px;
  padding: 12px 16px;
  text-decoration: none;
  display: block;
  text-align: left;
  font-weight:normal;
}
a.menu:hover , a.icon:hover, .dropdown:hover .dropbtn {
  padding-bottom: 20px;
  border-bottom: 5px solid #55ff00;

}

.dropdown-content a:hover {
  background-color: #ddd;
  color: black;
}

.dropdown:hover .dropdown-content {
  display: block;
}
@media screen and (max-width: 1000px) {
  .topnav a:not(:first-child), .dropdown .dropbtn {
    display: none;
  }
  .topnav a.icon {
    float: right;
    display: block;
  }
}
@media screen and (max-width: 1000px) {
  .topnav.responsive {
    position: relative;
    background-color:hsla(0,0%,100%,1);
}
  
.topnav.responsive .icon {
    position: absolute;
    right: 0;
    top: 0;
  }
  .topnav.responsive a {
    float: none;
    display: block;
    text-align: left;
  }
  .topnav.responsive .dropdown {float: none;}
  .topnav.responsive .dropdown-content {position: relative;}
  .topnav.responsive .dropdown .dropbtn {
    display: block;
    width: 100%;
    text-align: left;
  }
}