এইচটিএমএল

<div class="parent">
  <header class="section yellow">Header</header>
  <main class="section blue">Main</main>
  <footer class="section green">Footer Content</footer>
</div>

সিএসএস


        .parent {
  display: grid;
  grid-template-rows: auto 1fr auto;

  /* Just for parent demo size */
  height: 100vh;
}