$(document).ready(function(){
$("#desc1").css({ "visibility": "visible" });
$("#desc2").css({ "visibility": "hidden" });
$("#desc3").css({ "visibility": "hidden" });
$("#desc4").css({ "visibility": "hidden" });

   $("a.tab1").click(
      function () {
        $("a.tab1").animate({opacity: 1}, 700 );
		$("a.tab2").animate({opacity: 0.6}, 700 );
		$("a.tab3").animate({opacity: 0.6}, 700 );
		$("a.tab4").animate({opacity: 0.6}, 700 );
        $("#desc1").css({ "visibility": "visible" });
        $("#desc2").css({ "visibility": "hidden" });
        $("#desc3").css({ "visibility": "hidden" });
        $("#desc4").css({ "visibility": "hidden" });
      }
          );
    
    $("a.tab2").click(
      function () {
		$("a.tab1").animate({opacity: 0.6}, 700 );
		$("a.tab2").animate({opacity: 1}, 700 );
		$("a.tab3").animate({opacity: 0.6}, 700 );
		$("a.tab4").animate({opacity: 0.6}, 700 );
		$("#desc1").css({ "visibility": "hidden" });
        $("#desc2").css({ "visibility": "visible" });
        $("#desc3").css({ "visibility": "hidden" });
        $("#desc4").css({ "visibility": "hidden" });
      }
      
    );
    
    $("a.tab3").click(
      function () {
		$("a.tab1").animate({opacity: 0.6}, 700 );
		$("a.tab2").animate({opacity: 0.6}, 700 );
		$("a.tab3").animate({opacity: 1}, 700 );
		$("a.tab4").animate({opacity: 0.6}, 700 );
        $("#desc1").css({ "visibility": "hidden" });
        $("#desc2").css({ "visibility": "hidden" });
        $("#desc3").css({ "visibility": "visible" });
        $("#desc4").css({ "visibility": "hidden" });
      } 
      
    );
    
    $("a.tab4").click(
      function () {
		$("a.tab1").animate({opacity: 0.6}, 700 );
		$("a.tab2").animate({opacity: 0.6}, 700 );
		$("a.tab3").animate({opacity: 0.6}, 700 );
		$("a.tab4").animate({opacity: 1}, 700 );
        $("#desc1").css({ "visibility": "hidden" });
        $("#desc2").css({ "visibility": "hidden" });
        $("#desc3").css({ "visibility": "hidden" });
        $("#desc4").css({ "visibility": "visible" });
      }
      
    );
    

  });