document.addEventListener('DOMContentLoaded', function() {

    const sidebarItemsWithSub = document.getElementsByClassName('js-sidebar-item-with-submenu');
    let sidebarItemsWithSubLength = sidebarItemsWithSub.length;
    for(let i = 0; i < sidebarItemsWithSubLength; i++){

        const sidebarItemWithSub = sidebarItemsWithSub[i];
        const sidebarSubmenuToggle =  sidebarItemWithSub.querySelector('.js-toggle-list');
        sidebarSubmenuToggle.addEventListener('click', function () {

            const sidebarItem = this.parentElement;
            const sidebarItemSubmenu = sidebarItem.querySelector('.js-sidebar-submenu');
            sidebarItemSubmenu.classList.toggle('is-open');
        });
    }

});