Responsive menu

Submenu voor desktop en mobile.

HTML

<meta name="viewport" content="width=device-width, initial-scale=1">
<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/font-awesome/4.7.0/css/font-awesome.min.css">

<div class="topnav" id="myTopnav">

  <a href="#home" class="active">Home</a>
  
  <a href="#news">Blablablagroen</a>
  
  <a href="#news">Holderdebolder</a>
  
  <a href="#news">Beste_van_het_beste</a>
  
  <div class="newsbrieven">
     <button class="newsbtn">Newsbrieven 
      <i class="fa fa-caret-down"></i>
    </button>
    <div class="newsbrieven-content">
      <a href="#">NewsLink 1</a>
      <a href="#">NewsLink 2</a>
      <a href="#">NewsLink 3</a>
      
      <a href="#">NewsLink 4</a>
      <a href="#">NewsLink 5</a>
           
    </div>
  </div>
  
  <a href="#contact">Contactueel</a>
  
  <div class="dropdown">
    <button class="dropbtn">Dropdown 
      <i class="fa fa-caret-down"></i>
    </button>
    <div class="dropdown-content">
      <a href="#">Link 1</a>
      <a href="#">Link 2</a>
      <a href="#">Link 3</a>
      
      <a href="#">Link 4</a>
      <a href="#">Link 5</a>
           
    </div>
  </div> 
  <a href="#about">About</a>
  <a href="javascript:void(0);" style="font-size:15px;" class="icon" onclick="myFunction()">☰</a>
</div>

<div style="padding-left:16px">
  <h2>Responsive Topnav with Dropdown</h2>
  <p>Resize the browser window to see how it works.</p>
  <p>Hover over the dropdown button to open the dropdown menu.</p>
</div>

CSS

body {
  margin: 0;
  font-family: Arial;
}
.topnav {
  overflow: hidden;
  background-color: #333;
}
.topnav a {
  float: left;
  display: block;
  color: #f2f2f2;
  text-align: center;
  padding: 14px 16px;
  text-decoration: none;
  font-size: 17px;
}
.active {
  background-color: #04AA6D;
  color: white;
}
.topnav .icon {
  display: none;
}
.newsbrieven {
  float: left;
  overflow: hidden;
}
.newsbrieven .newsbtn {
  font-size: 17px;
  border: none;
  outline: none;
  color: white;
  padding: 14px 16px;
  background-color: inherit;
  font-family: inherit;
  margin: 0;
}
.newsbrieven-content {
  display: none;
  position: absolute;
  background-color: #f9f9f9;
  min-width: 160px;
  box-shadow: 0px 8px 16px 0px rgba(0,0,0,0.2);
  z-index: 1;
}
.newsbrieven-content a {
  float: none;
  color: black;
  padding: 12px 16px;
  text-decoration: none;
  display: block;
  text-align: left;
}
.topnav a:hover, .newsbrieven:hover .newsbtn {
  background-color: #555;
  color: white;
}
.newsbrieven-content a:hover {
  background-color: #ddd;
  color: black;
}
.newsbrieven:hover .newsbrieven-content {
  display: block;
}
.dropdown {
  float: left;
  overflow: hidden;
}
.dropdown .dropbtn {
  font-size: 17px;
  border: none;
  outline: none;
  color: white;
  padding: 14px 16px;
  background-color: inherit;
  font-family: inherit;
  margin: 0;
}
.dropdown-content {
  display: none;
  position: absolute;
  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;
  padding: 12px 16px;
  text-decoration: none;
  display: block;
  text-align: left;
}
.topnav a:hover, .dropdown:hover .dropbtn {
  background-color: #555;
  color: white;
}
.dropdown-content a:hover {
  background-color: #ddd;
  color: black;
}
.dropdown:hover .dropdown-content {
  display: block;
}
@media screen and (max-width: 600px) {
  .topnav a:not(:first-child), .newsbrieven .newsbtn .dropdown .dropbtn {
 ...

JavaScript

function myFunction() {
  var x = document.getElementById("myTopnav");
  if (x.className === "topnav") {
    x.className += " responsive";
  } else {
    x.className = "topnav";
  }
}