<?php

wp_nav_menu(
  array(
    'theme_location' => 'main_menu',
    'container'      => false,
    'menu_class'     => 'menu-overlay js-menu-overlay',
    'link_before'    => '<div class="menu-overlay__item-wrapper split-text js-split-text" data-split-text-type="lines">',
    'link_after'     => '</div>',
    'walker'         => new Arts_Walker_Nav_Menu_Overlay(),
  )
);