title: Bootstrap. Make vertical browser scrollbar start under fixed navbar. (not overlap)
body: <p>I'm using an example code for a fixed navbar provided by bootstrap. Is there any relatively easy way to make a browser scrollbars not overlap a fixed navbar.</p>
  
  <p>Here is how it is in example:
  <img src="https://i.stack.imgur.com/wCEVt.png" alt="http://i.stack.imgur.com/wCEVt.png"></p>
  
  <p>Here is what I'm trying to get:
  <img src="https://i.stack.imgur.com/GY0km.png" alt="http://i.stack.imgur.com/GY0km.png"></p>
  
  <p>Thanks a lot in advance.
  Regards.</p>