registerClassNames(parent) {

    const addClass = $tw.utils.addClass;

    // add main class
    addClass(parent, 'tmap-widget');

    if (this.clickToUse) {
      addClass(parent, 'tmap-click-to-use');
    }

    if (this.getAttr('editor') === 'advanced') {
      addClass(parent, 'tmap-advanced-editor');
    }

    if (this.getAttr('design') === 'plain') {
      addClass(parent, 'tmap-plain-design');
    }

    if (!utils.isTrue(this.getAttr('show-buttons'), true)) {
      addClass(parent, 'tmap-no-buttons');
    }

    if (this.getAttr('class')) {
      addClass(parent, this.getAttr('class'));
    }

  }
Add some classes to give the user a chance to apply some css
to different graph modes.