title: Bootstrap container, grid rows width and a padding issue
body: <p>I'm creating my first bootstrap frontend, and I'm experiencing some issues which I'm not able to solve:</p>
  
  <p><a href="https://i.stack.imgur.com/az6go.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/az6go.png" alt="row"></a></p>
  
  <p>The row expanding to the whole width of the container, the max column width (12 units) will not extend to this width:</p>
  
  <p><a href="https://i.stack.imgur.com/3vMXm.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/3vMXm.png" alt="column"></a></p>
  
  <p>Further on, why is  within the container writing over the padding:</p>
  
  <p><a href="https://i.stack.imgur.com/vx9ne.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/vx9ne.png" alt="padding"></a></p>
  
  <p>Any hints appreciated!</p>
  
  <p>I already tried to use container-fluid class, but the row seems not to get the max width.</p>
  
  <p>Whole HTML:</p>
  
  <pre><code>&lt;!DOCTYPE html&gt;
  &lt;html&gt;
  &lt;head&gt;
      &lt;title&gt;Snoo&lt;/title&gt;
  
      &lt;link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-beta.2/css/bootstrap.min.css" integrity="sha384-PsH8R72JQ3SOdhVi3uxftmaW6Vc51MKb0q5P2rRUpPvrszuE4W1povHYgTpBfshb" crossorigin="anonymous"&gt;
  
      &lt;link rel="stylesheet" type="text/css" href="app.css"&gt;
  
  &lt;/head&gt;
  &lt;body&gt;  
      &lt;div class="container"&gt;
          &lt;nav class="navbar navbar-expand-lg navbar-light bg-light"&gt;
              &lt;a class="navbar-brand" href="#"&gt;Snoo!&lt;/a&gt;
              &lt;button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarSupportedContent" aria-controls="navbarSupportedContent" aria-expanded="false" aria-label="Toggle navigation"&gt;
                  &lt;span class="navbar-toggler-icon"&gt;&lt;/span&gt;
              &lt;/button&gt;
  
              &lt;div class="collapse navbar-collapse" id="navbarSupportedContent"&gt;
                  &lt;ul class="navbar-nav mr-auto"&gt;
                      &lt;li class="nav-item"&gt;
                          &lt;a class="nav-link" href="#"&gt;About&lt;/a&gt;
                      &lt;/li&gt;
                      &lt;li class="nav-item"&gt;
                          &lt;a class="nav-link" href="#"&gt;Reddit!&lt;/a&gt;
                      &lt;/li&gt;
                  &lt;/ul&gt;
              &lt;/div&gt;
          &lt;/nav&gt;
      &lt;/div&gt;
  
      &lt;div class="container"&gt; 
          &lt;div class="row"&gt;           
              &lt;div class="col_xl-12"&gt;     
                  &lt;div id="content"&gt;      
                      &lt;h1&gt;Snoo!&lt;/h1&gt;
                      &lt;hr&gt;
                      &lt;h3&gt;A chatbot based on a million reddit comments, quiet salty!&lt;/h3&gt;
                      &lt;button class="btn btn-primary btn-lg"&gt;Learn more!&lt;/button&gt;
                  &lt;/div&gt;
              &lt;/div&gt;
          &lt;/div&gt;
      &lt;/div&gt;
  &lt;/body&gt;
  
  &lt;script src="https://code.jquery.com/jquery-3.2.1.slim.min.js" integrity="sha384-KJ3o2DKtIkvYIK3UENzmM7KCkRr/rE9/Qpg6aAZGJwFDMVNA/GpGFF93hXpG5KkN" crossorigin="anonymous"&gt;&lt;/script&gt;
  &lt;script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.12.3/umd/popper.min.js" integrity="sha384-vFJXuSJphROIrBnz7yo7oB41mKfc8JzQZiCq4NCceLEaO4IHwicKwpJf9c9IpFgh" crossorigin="anonymous"&gt;&lt;/script&gt;
  &lt;script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-beta.2/js/bootstrap.min.js" integrity="sha384-alpBpkh1PFOepccYVYDB4do5UnbKysX5WZXm3XxPqe5iKTfUKjNkCk9SaVuEZflJ" crossorigin="anonymous"&gt;&lt;/script&gt;
  
  &lt;/html&gt;
  </code></pre>
  
  <p>css:</p>
  
  <pre><code>#content {
      text-align: center;
      padding-top: 25%
  }
  </code></pre>