/*
 * Open the drawer when the menu icon is clicked.
 */
 function openDrawer() {
   var menu = document.querySelector('#menu');
   var container = document.querySelector('.container');
   var drawer = document.querySelector('.nav');

   menu.addEventListener('click', function(e) {
     drawer.classList.toggle('open');
     e.stopPropagation();
   });
   container.addEventListener('click', function() {
     drawer.classList.remove('open');
   });
 };
