SOURCE

function positionFooter() {
  var footer = $("#fd");
  if ((($(document.body).height() + footer.outerHeight()) < $(window).height() && footer.css("position") == "fixed") || ($(document.body).height() < $(window).height() && footer.css("position") != "fixed")) {
    footer.css({
      position: "fixed",
      bottom: "0",
      width: '100%'
    });
  } else {
    footer.css({
      position: "static"
    });
  }
}
function stickFooter() {
  $(window).scroll(positionFooter).load(positionFooter).resize(positionFooter);
}
stickFooter();