Как в botstrap уменьшить высоту section class="jumbotron?

Question

Kvandaik @Kvandaik

HTML
CSS

Как в botstrap уменьшить высоту section class="jumbotron?

<!doctype html>
<html lang="en">
  <head>
    <!-- Required meta tags -->
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
    <link rel="icon" href="http://vladmaxi.net/favicon.ico" type="image/x-icon">
		<link rel="shortcut icon" href="http://vladmaxi.net/favicon.ico" type="image/x-icon">
		<link rel="stylesheet" type="text/css" href="css/default.css" />
		<link rel="stylesheet" type="text/css" href="css/component.css" />
		<link rel="stylesheet" type="text/css" href="css/style.css" />
		<link rel="stylesheet" type="text/css" href="css/styles.css" />
		<script type='text/javascript' src='js/select.js'></script>

    <!-- Bootstrap CSS -->
    <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/css/bootstrap.min.css" integrity="sha384-Gn5384xqQ1aoWXA+058RXPxPg6fy4IWvTNh0E263XmFcJlSAwiGgFAW/dAiS6JXm" crossorigin="anonymous">

    <title>Main</title>
  </head>
  <body>
<header>
      <div class="bg-dark collapse" id="navbarHeader" style="">
        <div class="container">
          <div class="row">
            <div class="col-sm-8 col-md-7 py-4">
              <h4 class="text-white">Привет,
         </h4>
              <p class="text-muted"></p>
            </div>
            <div class="col-sm-4 offset-md-1 py-4">
              <h4 class="text-white">Contact</h4>
              <ul class="list-unstyled">
                <li><a href="#" class="text-white">21</a></li>
                <li><a href="#" class="text-white"></a></li>
                <li><a href="#" class="text-white">www</a></li>
              </ul>
            </div>
          </div>
        </div>
      </div>
      <div class="navbar navbar-dark bg-dark box-shadow">
        <div class="container d-flex justify-content-between">
          <a href="#" class="navbar-brand d-flex align-items-center">
            <strong>=)</strong>
          </a>
          <button class="navbar-toggler collapsed" type="button" data-toggle="collapse" data-target="#navbarHeader" aria-controls="navbarHeader" aria-expanded="false" aria-label="Toggle navigation">
            <span class="navbar-toggler-icon"></span>
          </button>
        </div>
      </div>
    </header>
<section class="jumbotron text-center">
  <div class="container">
<h1 class="jumbotron-heading">Добро пожаловать: 

</h1>

    </p>
  </div>
</section>
<br>
<br>
<br>
<br>
<br>
<br>
<center>
<h3 class="jumbotron-heading">В</h3>
</center>

</form>

</main>

        <br>

    <script src="https://code.jquery.com/jquery-3.2.1.slim.min.js" integrity="sha384-KJ3o2DKtIkvYIK3UENzmM7KCkRr/rE9/Qpg6aAZGJwFDMVNA/GpGFF93hXpG5KkN" crossorigin="anonymous"></script>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.12.9/umd/popper.min.js" integrity="sha384-ApNbgh9B+Y1QKtv3Rn7W3mgPxhU9K/ScQsAP7hUibX39j7fakFPskvXusvfa0b4Q" crossorigin="anonymous"></script>
    <script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/js/bootstrap.min.js" integrity="sha384-JZR6Spejh4U02d8jOt6vLEHfe/JQGiRRSQQxSfFWpi1MquVdAyjUar5+76PVCmYl" crossorigin="anonymous"></script>
	<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.4.3/jquery.min.js"></script>
	<script src="js/script.js"></script>
  </body>