$(document).ready(function(){
	
  if(document.getElementById('gallery_ul')) { var wb = document.getElementById('gallery_ul').clientWidth - document.getElementById('gallery').clientWidth; }
  var a = 0, ws = 448;
  
  $(".left_arrow").click(function(){	
    a = a - ws;
	if(a >= 0)
	{
	  $("#gallery_ul").animate({left: "+=448"}, "slow");
	  document.getElementById("right_arrow").style.backgroundPosition = "";
	  document.getElementById("right_arrow").style.cursor = "pointer";
	  
	}
	else
	{
	  a = 0;
	  document.getElementById("left_arrow").style.backgroundPosition = "-38px 0";
	  document.getElementById("left_arrow").style.cursor = "default";
	}

  });
  
  $(".right_arrow").click(function(){		
    a = a + ws; 
    if(a <= wb)
	{
      $("#gallery_ul").animate({left: "-=448"}, "slow");
	  document.getElementById("left_arrow").style.backgroundPosition = "";
	  document.getElementById("left_arrow").style.cursor = "pointer";
	}
	else
	{
	  a = a - ws;
	  document.getElementById("right_arrow").style.backgroundPosition = "-38px 0";
	  document.getElementById("right_arrow").style.cursor = "default";
	}
  
  });
  
});