Anyone see why this code might not work?

Anyone see why this code might not work?

this code works:

  2. $('#offer span').click(function(){    
  3.     var $divx = $('#offerbody').first();
  4.     $(this).html( $divx.is(':visible') ? ' [+] ' : ' [–] ');
  5.     $divx.slideToggle(); 
  6. });


this code does nothing (I was hoping it would make the div hidden):

  2. $(document).ready(function () {  
  3.   var $divx = $('#offerbody').first(); 
  4.       $divx.css('visibility','hidden'); 
  5.       $(this).html( $divx.is(':visible') ? ' [+] ' : ' [–] '); 
  6.           
  7. });