material_base-8.x-2.x-dev/themes/material_base_mdc/templates/layout/region--navbar.html.twig

{#
/**
 * @file
 * Theme override to display a region.
 *
 * Available variables:
 * - content: The content for this region, typically blocks.
 * - attributes: HTML attributes for the region <div>.
 * - region: The name of the region variable as defined in the theme's
 *   .info.yml file.
 *
 * @see template_preprocess_region()
 */
#}
{% set classes = [
    'region',
    'region-' ~ region|clean_class,
    'page-navbar',
    'navbar',
    'mdc-top-app-bar',
    navbar_fixed ? 'mdc-top-app-bar--fixed' : 'mdc-top-app-bar--not-fixed',
    navbar_style ? 'mdc-top-app-bar--' ~ navbar_style,
] %}

{% if content %}
  <header{{ attributes.addClass(classes).setAttribute('data-mdc-auto-init', 'MDCTopAppBar') }}>
    <div class="navbar__container mdc-top-app-bar__row">
      <section class="navbar__section mdc-top-app-bar__section">
        {{ content }}
      </div>
    </section>
  </header>
{% endif %}