function main(){
    var lastScrollTop = 0;
    var animationEnd = 'animationend oAnimationEnd mozAnimationEnd webkitAnimationEnd';
    $(document).scroll( _.throttle(function() {
      var st = $(this).scrollTop();
      if ( st > lastScrollTop )
      {
        runAnimation("#home-header", "slideOutUp faster");
      }
      else
      {
        runAnimation("#home-header", "slideInDown faster");
      }
      lastScrollTop = st;
    }, 500
  ));

    function runAnimation(element, animationName) {
        $(element).removeClass("animated slideInDown slideOutUp");
        $(element).addClass("animated " +animationName).one(animationEnd, function() {
          animationRunning = false;
        });
    }

  }

  $(document).ready(main);