Bootstrap Carousel horizontal gray bar on the bottom

Hi guys,

I am just trying to customize bootstrap carousel but for some reason i have horizontal gray bar on the bottom below every picture and I can't get rid of it. This is my code:

     <!----carousel-->
      <section class= "bg-dark rounded ">
      
      
          <div class="container mt-2 bg-warning ">
        <div id="carouselExampleCaptions" class="carousel slide" data-ride="carousel">
          <ol class="carousel-indicators">
            <li data-target="#carouselExampleCaptions" data-slide-to="0" class="active"></li>
            <li data-target="#carouselExampleCaptions" data-slide-to="1"></li>
            <li data-target="#carouselExampleCaptions" data-slide-to="2"></li>
          </ol>
          <div class="carousel-inner">
            <div class="carousel-item active">
              <img src="images/1.jpg" class="d-block w-100" alt="...">
              <div class="carousel-caption d-none d-md-block  title-bg">
                <h5>News 1</h5>
                <p>Title goes here...</p>
              </div>
            </div>
            <div class="carousel-item">
              <img src="images/2.jpg" class="d-block w-100" alt="...">
              <div class="carousel-caption d-none d-md-block title-bg">
                <h5>News 2 </h5>
                <p>Title goes here...</p>
              </div>
            </div>
            <div class="carousel-item">
              <img src="images/3.jpg" class="d-block w-100" alt="...">
              <div class="carousel-caption d-none d-md-block title-bg shadow-sm ">
                <h5>News 3</h5>
                <p>Title goes here....</p>
              </div>
            </div>
          </div>
          <a class="carousel-control-prev" href="#carouselExampleCaptions" 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="#carouselExampleCaptions" role="button" data-slide="next">
            <span class="carousel-control-next-icon" aria-hidden="true"></span>
            <span class="sr-only">Next</span>
          </a>
        </div>
      </div> 
      </section>

Any help will be appreciated. Thank you very much in advance