// JavaScript Document
  var SlideWidth = 548;
   var SlideSpeed = 500;
      function CurrentMargin() {
            var currentMargin = $("#slider-wrapper").css("margin-left");
	           if (currentMargin == "auto") {
                	currentMargin = 0;
            	}            
            return parseInt(currentMargin);
        }       

        function NextSlide() {
            var newMargin = CurrentMargin() - SlideWidth;
           	$("#slider-wrapper").animate({ marginLeft: newMargin }, SlideSpeed);
        }

        function PreviousSlide() {
           var newMargin = CurrentMargin() + SlideWidth;
            $("#slider-wrapper").animate({ marginLeft: newMargin }, SlideSpeed);
        }