title: Position a background using bootstrap
body: <p>I'm using Bootstrap (3 or 4), and would like to have a diagonal line that runs across the full width of the page, with a middle that stays more or less in the center of a fixed-width content area (sometimes text, sometimes image), even as the browser window is resized. I have an image of how I imagine this to look when done:</p>
  
  <p><a href="http://i.stack.imgur.com/Z6LYz.png" rel="nofollow">An image of what this looks like</a></p>
  
  <p>I've been using a triangle-shaped white SVG to make the angle, but I'm having trouble keeping it in frame. The angle of the line should remain the same no matter what the window size is.</p>