title: HTML / CSS Fullscreen layout width 3 columns
body: <p>I'm stuck with a problem. How to make full screen layout, where left and right columns are fixed width (for example 250px), but middle column is fluid. My page must be always be full screen!
  I want something like this:</p>
  
  <p><img src="https://i.stack.imgur.com/blVuM.png" alt="screen layout"></p>