Prueba margins

by Christian Unigarro

HTML

<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/css/bootstrap.min.css">
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/js/bootstrap.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/3.0.0-beta1/jquery.min.js"></script>
<div class="container">
  <div class="alert-wrapper">
    <div class="alert alert-warning alert-dismissible" role="alert">
      <button type="button" class="close" data-dismiss="alert" aria-label="Close">
        <span aria-hidden="true">&times;</span>
      </button>
      <strong>Warning!</strong> Better check yourself, you're not looking too good.
    </div>
  </div>
  <div class="row element-bottom">
    <div class="col-xs-12">
      Lorem ipsum dolor sit amet, consectetur adipisicing elit. Vel asperiores officia nostrum distinctio, aliquam enim perspiciatis aperiam vero odio totam. Itaque laudantium blanditiis nemo laboriosam ea reprehenderit quas voluptas magni.
    </div>
  </div>
</div>

CSS

.alert-wrapper {
  margin-bottom: 50px;
}