<header>
  <div id="carouselExampleIndicators" class="carousel slide" data-ride="carousel">
    <ol class="carousel-indicators">
      <li data-target="#carouselExampleIndicators" data-slide-to="0" class="active"></li>
      <li data-target="#carouselExampleIndicators" data-slide-to="1"></li>
      <li data-target="#carouselExampleIndicators" data-slide-to="2"></li>
    </ol>
    <div class="carousel-inner" role="listbox">
      <!-- Slide One - Set the background image for this slide in the line below -->
      <div class="carousel-item active" style="background-image: url(<%= asset_url('img1.jpg')%>)">
      </div>
      <!-- Slide Two - Set the background image for this slide in the line below -->
      <div class="carousel-item" style="background-image: url(<%= asset_url('img2.jpg')%>)">
      </div>
      <!-- Slide Three - Set the background image for this slide in the line below -->
      <div class="carousel-item" style="background-image: url(<%= asset_url('img3.jpg')%>)">
      </div>
    </div>
    <a class="carousel-control-prev" href="#carouselExampleIndicators" role="button" data-slide="prev">
      <span class="carousel-control-prev-icon" aria-hidden="true"></span>
      <span class="sr-only">Previous</span>
    </a>
    <a class="carousel-control-next" href="#carouselExampleIndicators" role="button" data-slide="next">
      <span class="carousel-control-next-icon" aria-hidden="true"></span>
      <span class="sr-only">Next</span>
    </a>
  </div>
</header>