Bulma class: .hero.is-fullheight-with-navbar

<section class="hero is-link is-fullheight-with-navbar">
  <div class="hero-body">
    <div class="container">
      <p class="title">
        Fullheight hero with navbar
      </p>
    </div>
  </div>
</section>

Preview

More in Bulma Hero