fonteva-design-guide/force-app/main/default/lwc/pfmMenu/pfmMenu.js

## Dev, Build and Test

import { LightningElement, api, track } from 'lwc';
export default class Menu extends LightningElement {
    @api menuList;
    @api active;
    @api selectFirst;
    @api vertical = false;

    @track classes;

    renderedCallback() {
        let vertical = this.vertical ? ' pfm-menu_vertical' : '';
        this.classes = 'pfm-menu' + vertical;
    }
    checkValue(event) {
        this.changeSelected(event);
        const checkingValue = new CustomEvent('display', {
            detail: {
                item: event.target.dataset.item,
                route: event.target.dataset.route,
                selected: event.target.dataset.selected
            }
        });
        this.dispatchEvent(checkingValue);
    }
    changeSelected(event) {
        const item = event.currentTarget,
            allItems = this.template.querySelectorAll('a');
        allItems.forEach(function (i) {
            i.classList.remove('js-selected');
        });

        item.classList.add('js-selected');
    }
}