#en {
  display: none;
}

.button_lang {
  background-color: #444;
  color: #FFF;
  padding: 8px 20px;
  border-radius: 5px;
    
  -webkit-transition: background-color .3s ease-in-out;
  -moz-transition: background-color .3s ease-in-out;
  -o-transition: background-color .3s ease-in-out;
  -ms-transition: background-color .3s ease-in-out;
  transition: background-color .3s ease-in-out;
}
.button_lang:hover, .current_lang {
  background-color: #777;   
  -webkit-transition: background-color .3s ease-in-out;
  -moz-transition: background-color .3s ease-in-out;
  -o-transition: background-color .3s ease-in-out;
  -ms-transition: background-color .3s ease-in-out;
  transition: background-color .3s ease-in-out;
}
ul li {
  width: auto;
  display: inline;
}