Bootstrap CSS class .carousel-fade

<div id="carouselFadeExampleIndicators" class="carousel slide carousel-fade" data-ride="carousel">
  <div class="carousel-inner" role="listbox">
    <div class="carousel-item active">
      <img class="d-block w-100" src="#" src="/placeholder/pictures/image.svg" alt="First slide">
    </div>
    <div class="carousel-item">
      <img class="d-block w-100" src="#" src="/placeholder/pictures/image.svg" alt="Second slide">
    </div>
  </div>
  <a class="carousel-control-prev" href="#carouselFadeExampleIndicators" 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="#carouselFadeExampleIndicators" role="button" data-slide="next">
    <span class="carousel-control-next-icon" aria-hidden="true"></span>
    <span class="sr-only">Next</span>
  </a>
</div>