<div class="d-flex flex-column h-100">
  <header class="text-center bg-dark text-white">
    <h1 class="d-flex"><span class="flex-grow-1">Header</span><button class="btn btn-sm btn-primary" id="toggle">Toggle Content</button></h1>
  </header>
  <section class="container-one flex-grow-1 bg-secondary">
    Section 1
  </section>
  <section class="container-two flex-grow-1 bg-primary text-white">
    Section 2
  </section>
  <footer class="bg-primary bg-dark text-white">
    Copyright &copy; 2020
  </footer>
</div>

Select all