epfl-theme-elements/src/includes/partials/back-to-top-en.html

EPFL Web 2018 Styleguide based on elements

<button id="back-to-top" class="btn btn-primary btn-back-to-top">
  <span class="sr-only">Back to top</span>
  <svg class="icon" aria-hidden="true">
    <use xlink:href="#icon-chevron-top"></use>
  </svg>
</button>