How to configure submenu with full width

I used the following code to get full width sub-menus. This code was borrowed and modified from the hollyhunt site.
I'm using tb_megamenu version 2.0.0-alpha3

global.js in my site's theme
dynamically sets the menu width and left offset

/**
 * @file
 * Global utilities.
 *
 */
(function ($, Drupal) {

  'use strict';

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

        // Make submenu full browser width.
        const submenuFullwidthCalc = function () {
          // Get the Mega menu Level 1 sub menu.
          $(".tbm-nav > .level-1 > .tbm-submenu").each(function () {
            // reset to zero so it can be calculated again and again
            $(this).css("left", 0);
            const offsettarget = $("body").offset();
            // The offset of this submenu.
            const offsetthis = $(this)
              //.parent()
              .parents( "ul" ) // get parent ul instead
              .offset();
            // Calculate the offset.
            $(this).css("left", offsettarget.left - offsetthis.left);

            // Set the submenu full width.
            $(this).css("width", $("body").width());
          });
        };

        $(window).on("load resize", function () {
          submenuFullwidthCalc();
        });

    }



  };

})(jQuery, Drupal);

The below is not necessary but helps with formatting to prevent content from stretching to the edges.

customized tb-megamenu-submenu.html.twig

<div {{ attributes }}>
  <div class="tb-dropdown-inner">
    {% for row in rows %}
      {{ row }}
    {% endfor %}
  </div>
</div>

CSS

.tb-dropdown-inner {
	max-width: 1278px;
	margin: auto;
	padding: 0 45px 28px;
	min-height: 200px;
}