Bootstrap vertical align using center-block
<p>I've made div with bootstrap class attribute center-block and I want to align it vertically but nothing is working only manually adding margin to the div. Any tips how to accomplish this ? 
Css code:</p>

<pre><code>body {
  margin-bottom: 31px;
  font-family: 'Lato', sans-serif;
}
.footer {
  position: absolute;
  bottom: 0;
  width: 100%;
  height: 31px;
  border-top: 1px solid white;
}
.menu{
  width: 642px;
  height: 642px;
  border: 1px solid white;

}
.menu &gt; p{
  width: 300px;
  height: 300px;
  margin: 10px;
  float: left;
  color: white;
  text-align: center;
  font-size: 28px;
  text-shadow: 2px 2px 5px black;
}
</code></pre>

<p><br>
Html code:</p>

<pre><code>     &lt;!DOCTYPE html&gt;
    &lt;html lang="en"&gt;
    &lt;head&gt;
  &lt;meta charset="UTF-8"&gt;
  &lt;meta name="viewport" content="width=device-width, initial-scale=1.0"&gt;
  &lt;meta http-equiv="X-UA-Compatible" content="ie=edge"&gt;
  &lt;link rel="stylesheet" type="text/css" href="css/style.css"&gt;
  &lt;script src="https://ajax.googleapis.com/ajax/libs/jquery/3.1.1/jquery.min.js"&gt;&lt;/script&gt;
  &lt;link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css" integrity="sha384-BVYiiSIFeK1dGmJRAkycuHAHRg32OmUcww7on3RYdg4Va+PmSTsz/K68vbdEjh4u" crossorigin="anonymous"&gt;
  &lt;link href="https://fonts.googleapis.com/css?family=Lato" rel="stylesheet"&gt;
      &lt;style&gt;
      body{
        background-image: url(img/landscape1.jpg);
        background-size: cover;
      }
      &lt;/style&gt;
      &lt;title&gt;Website&lt;/title&gt;
    &lt;/head&gt;
    &lt;body&gt;
      &lt;div class="container-fluid"&gt;
        &lt;div class="page-header"&gt;
          &lt;h1 style="color: white;"&gt;Logo&lt;/h1&gt;
        &lt;/div&gt;
        &lt;div class="center-block menu"&gt;
          &lt;p id=""&gt;demo1&lt;/p&gt;
          &lt;p id=""&gt;demo2&lt;/p&gt;
          &lt;p id=""&gt;demo3&lt;/p&gt;
          &lt;p id=""&gt;demo4&lt;/p&gt;
        &lt;/div&gt;
      &lt;/div&gt;
        &lt;footer class="footer"&gt;
            &lt;div class="container col-lg-6 col-md-6 col-sm-6 col-xs-6"&gt;
            &lt;p class="text-muted"&gt;Company all rights reserved &amp;copy; &lt;/p&gt;
          &lt;/div&gt;
        &lt;/footer&gt;





    &lt;script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js" integrity="sha384-Tc5IQib027qvyjSMfHjOMaLkfuWVxZxUPnCJA7l2mCWNIpG9mGCD8wGNIcPD7Txa" crossorigin="anonymous"&gt;&lt;/script&gt;
    &lt;/body&gt;
    &lt;/html&gt;
</code></pre>