title: how does one line up a responsive center column of specific width?
body: <p>I hate asking a "how do I do this" question, but I've tried everything I can think of and it's just not working.</p>
  
  <p>I have a page design in which there is a center column of specific width (960px) which needs to live in the horizontal center of the page as long as the browser is wider than that width.</p>
  
  <p>I'm entirely unclear on why, but every combination of columns and offsets I try leaves the content off center in one way or another.</p>
  
  <p>I know how to do this with margin:auto but then I lose bootstrap's auto-magical resizing of everything for mobile.</p>
  
  <p>So... is there a way to keep the responsive nature of the site as per bootstrap but to have it put the content into a center strip of a specific width (leaving the sides empty) and yet collapsing down to the -xs- variant when the page is pulled up on mobile?</p>