title: How to remove a gap between navbar and container-fluid?
body: <p>This is my case: <a href="http://codepen.io/gkos/pen/LxmrMP?editors=1100" rel="nofollow noreferrer">http://codepen.io/gkos/pen/LxmrMP?editors=1100</a></p>
  
  <pre><code>&lt;header&gt;
    &lt;nav class="navbar navbar-default"&gt;
      &lt;div class="container-fluid"&gt;
        &lt;ul class="nav navbar-nav"&gt;
          &lt;li class="navbar-text"&gt;Item&lt;/li&gt;
          &lt;li class="navbar-text"&gt;Item&lt;/li&gt;
          &lt;li class="navbar-text"&gt;Item&lt;/li&gt;
          &lt;li class="navbar-text"&gt;Item&lt;/li&gt;
        &lt;/ul&gt;
      &lt;/div&gt;
    &lt;/nav&gt;
  &lt;/header&gt;
  &lt;div class="site-content container-fluid"&gt;
    &lt;div class="row"&gt;
        &lt;div class="col-md-9"&gt;
          &lt;p&gt;Pellentesque habitant morbi tristique senectus et netus et malesuada fames ac turpis egestas. Vestibulum tortor quam, feugiat vitae, ultricies eget, tempor sit amet, ante. Donec eu libero sit amet quam egestas semper. Aenean ultricies mi vitae est. Mauris placerat eleifend leo. Quisque sit amet est et sapien ullamcorper pharetra. Vestibulum erat wisi, condimentum sed, commodo vitae, ornare sit amet, wisi. Aenean fermentum, elit eget tincidunt condimentum, eros ipsum rutrum orci, sagittis tempus lacus enim ac dui. Donec non enim in turpis pulvinar facilisis. Ut felis. Praesent dapibus, neque id cursus faucibus, tortor neque egestas augue, eu vulputate magna eros eu erat. Aliquam erat volutpat. Nam dui mi, tincidunt quis, accumsan porttitor, facilisis luctus, metus&lt;/p&gt;
      &lt;/div&gt;
      &lt;div class="col-md-3 site-sidebar"&gt;
        &lt;p&gt;Pellentesque habitant morbi tristique senectus et netus et malesuada fames ac turpis egestas. Vestibulum tortor quam, feugiat vitae, ultricies eget, tempor sit amet, ante. Donec eu libero sit amet quam egestas semper. Aenean ultricies mi vitae est. Mauris placerat eleifend leo. Quisque sit amet est et sapien ullamcorper pharetra. Vestibulum erat wisi, condimentum sed, commodo vitae, ornare sit amet, wisi. Aenean fermentum, elit eget tincidunt condimentum, eros ipsum rutrum orci, sagittis tempus lacus enim ac dui. Donec non enim in turpis pulvinar facilisis. Ut felis. Praesent dapibus, neque id cursus faucibus, tortor neque egestas augue, eu vulputate magna eros eu erat. Aliquam erat volutpat. Nam dui mi, tincidunt quis, accumsan porttitor, facilisis luctus, metus&lt;/p&gt;
      &lt;/div&gt;
    &lt;/div&gt;
  &lt;/div&gt;
  
  &lt;footer&gt;
    &lt;div class="container-fluid"&gt;
      &lt;div class="row navbar navbar-default"&gt;
        &lt;div class="col-md-4"&gt;&lt;p class="navbar-text"&gt;Pellentesque habitant morbi tristique senectus et netus et malesuada fames ac turpis egestas.&lt;/p&gt;&lt;/div&gt;
        &lt;div class="col-md-4"&gt;&lt;p class="navbar-text"&gt;Pellentesque habitant morbi tristique senectus et netus et malesuada fames ac turpis egestas.&lt;/p&gt;&lt;/div&gt;
        &lt;div class="col-md-4"&gt;&lt;p class="navbar-text"&gt;Pellentesque habitant morbi tristique senectus et netus et malesuada fames ac turpis egestas.&lt;/p&gt;&lt;/div&gt;
      &lt;/div&gt;
    &lt;/div&gt;
  &lt;/footer&gt;
  </code></pre>
  
  <p>I have a navbar, a container-fluid with two collons. There is a gap between navbar and the container showed in blue (the body background-color), how can I remove it so that the columns background color fill from navbar to footer wihtout gaps? I know about margin colapsing but I can't find any margin bean applied....</p>
  
  <p>Using negative margin in site-content class I could remove that gap, but I have to hardcode the gaps height in pixels and this seems not the right answer!</p>
  
  <pre><code>.site-content
    margin-top: -21px
  </code></pre>
  
  <p>Regards</p>