title: Uncaught TypeError: Cannot read property 'clientWidth' of null
body: <p>I have a responsive wordpress theme. The menu is coded to hide when the screen size is bellow 740. However it only does this correctly on the home page. If I go to any other page the menu collapses but it fails to hide and I get this error: "Uncaught TypeError: Cannot read property 'clientWidth' of null"</p>
  
  <p>Here's the code, I have it being called in the header.php file of the theme:</p>
  
  <pre><code>var ww = document.body.clientWidth;
  $(document).ready(function() {
      adjustMenu();
  
  
      $(".cat").click(function(e) { // cat class
          e.preventDefault();
          $(this).toggleClass("active");
          $(".sf-menu").toggle();
      });
  });
  
  function adjustMenu() {
      if (ww &lt;= 740) { //change this to your breakpoint
          $('.sf-menu').hide();
          $(".cat").show();
          if (!$(".cat").hasClass("active")) {
              $(".sf-menu").hide();
          } else {
              $(".sf-menu").show();
          }
      } else {
          $('.sf-menu').show();
          $(".cat").hide();
  
      }
  }
  
  
  $(window).bind('resize orientationchange', function() {
      ww = document.body.clientWidth;
      adjustMenu();
  });
  </code></pre>