<nav>
  <a href="#" id="toggle" class=""><span></span></a>
  <div id="menu" style="left: -2000px; opacity: 0;">
    <ul>
      <li><a href="#">Home</a></li>
      <li><a href="#">web design</a></li>
      <li><a href="#">édition</a></li>
      <li><a href="#">communication</a></li>
      <li><a href="#">photographies</a></li>
      <li class="contact1"><a href="designproduit.html">design produit</a></li>
    </ul>
  </div>
</nav>
<!-- Contenu de la page -->
<div id="content">
  <h1>Menu bar pour mobile</h1>
  <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit. Fugit consectetur modi omnis aut illo, officiis numquam rerum. Doloribus dignissimos quo quis, vero cumque provident quae officia error, unde ducimus reiciendis!</p>
  <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit. Fugit consectetur modi omnis aut illo, officiis numquam rerum. Doloribus dignissimos quo quis, vero cumque provident quae officia error, unde ducimus reiciendis!</p>
  <p>Lorem ipsum dolor sit amet, consectetur adipisicing elit. Fugit consectetur modi omnis aut illo, officiis numquam rerum. Doloribus dignissimos quo quis, vero cumque provident quae officia error, unde ducimus reiciendis!</p>
</div>
#toggle {
  display: block;
  width: 45px;
  height: 30px;
  margin-top: 0px;
  margin-bottom: 2px;
  position: absolute;
}
#toggle span:after, #toggle span:before {
  content: "";
  position: absolute;
  left: 0;
  top: -9px;
}
#toggle span:after {
  top: 9px;
}
#toggle span {
  position: relative;
  display: block;
  top: 20px;
}
#toggle span, #toggle span:after, #toggle span:before {
  width: 100%;
  height: 3px;
  background-color: #FF6B6B;;
  transition: all 0.2s;
  border-radius: 2px;
}
#toggle.on span:before {
  transform: rotate(45deg) translate(5px, 5px);
  -webkit-transform: rotate(45deg) translate(5px, 5px);
  -moz-transform: rotate(45deg) translate(5px, 5px);
  -o-transform: rotate(45deg) translate(5px, 5px);
  -ms-transform: rotate(45deg) translate(5px, 5px);
}
#toggle.on span:after {
  transform: rotate(-45deg) translate(7px, -8px);
  -webkit-transform: rotate(-45deg) translate(7px, -8px);
  -moz-transform: rotate(-45deg) translate(7px, -8px);
  -o-transform: rotate(-45deg) translate(7px, -8px);
  -ms-transform: rotate(-45deg) translate(7px, -8px);
}
#toggle.on span {
  background-color: transparent;
}
#menu {
  margin: 0;
  padding: 0;
  position: absolute;
  opacity: 0.3;
  top:30px;
  width: 180px;
  left: -850px;
  transition: all 0.3s ease;
  -webkit-transition: all 0.3s ease;
  -moz-transition: all 0.3s ease;
  -o-transition: all 0.3s ease;
  -ms-transition: all 0.3s ease;
  border: 1px solid #FF6B6B;;
  border-bottom: none;
  margin-top: 25px;
  background-color: rgb(240,240,240); 
}
#menu ul {
  margin: 0;
  padding: 0;
}
#menu li {
  border-bottom: 1px solid #FF6B6B;;
  list-style-type: none;
}
#menu li a {
  display: block;
  height: 40px;
  line-height: 40px;
  text-align: center;
  text-decoration: none;
  color: #353943;
  font-family: 'Hammersmith One', sans-serif;
  text-transform: uppercase;
  font-size: 14px;
  letter-spacing: 0.05em;
}
#menu li a:hover {
  opacity: 0.5;
}
/*
Contenu
*/

#content {
  padding: 60px;
  color: #353d46;
  font: 18px/27px 'Oxygen', sans-serif;
}
h1, h2, h3 {
  color: #FF6B6B;
  margin: 0 0 27px;
  line-height: 1em;
}
(function() {
  var theToggle = document.getElementById('toggle'); // cible toggle
  var theMenu = document.getElementById('menu'); // cible menu
  theToggle.bol = false; // interrupteur sur toogle
  theToggle.addEventListener('click', function(event){
    event.returnValue = false;
    this.bol = !this.bol; // inversion logique
    if(this.bol){ // test sur la variable - si vrai
      this.className = "on"; // rajout de la class
      theMenu.style.left = 0; // chgt propriété left sur le menu
      theMenu.style.opacity = 1; // chgt propriété opacity sur le menu
    }else{ // si faux
      this.className = ""; // remove class
      theMenu.style.left = '-2000px';
      theMenu.style.opacity = 0;
    }
  })
}).call(this);
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