<style>
  .slideshow-container {
    max-width: 100%;
    position: relative;
    margin: 2em auto;
  }

  .mySlides {
    display: none;
  }

  .fade {
    animation: fade 1s ease-in-out;
  }

  @keyframes fade {
    from { opacity: 0.4; }
    to   { opacity: 1; }
  }
</style>
