gistfile1.txt

function getMargin(section) {
  var viewPortHeight = $(window).height()
  var sectionHeight = $(section).height()
      , difference = (viewPortHeight - sectionHeight)
      , margin = (difference > 0) ? difference / 2 : 0
  // Max view height of 500 (divided by 2 is 250)
  return Math.min(250, margin)
}