drupal-erable/web/themes/erabletheme/js/erabletheme.js

/**
 * @file
 * erabletheme behaviors.
 */
(function (Drupal) {

  'use strict';

  Drupal.behaviors.erabletheme = {
    attach: function (context, settings) {

      const hamburgerBtn = document.getElementById("hamburger");
      const menu = hamburgerBtn.nextElementSibling;
    
      // Toggle menu visibility on hamburger click
      hamburgerBtn.addEventListener("click", function(event) {
        event.stopPropagation();
        menu.classList.toggle("active");
      });
    
      // Close menu when clicking outside of the menu
      document.addEventListener("click", function(event) {
        const isMenuClicked = event.target.closest("#menu") !== null;
        const isHamburgerClicked = event.target === hamburgerBtn;
    
        if (!isMenuClicked && !isHamburgerClicked) {
          menu.classList.remove("active");
        }
      });
    }
  };

} (Drupal));