how can i add classes to the content I'm trying to add class to the content, however its not adding anything 

    function themename_preprocess_page(&amp;$vars) {
      $is_sidebar_first_or_second= (empty($vars['page']['sidebar_first'])) || (empty($vars['page']['sidebar_second']));
      $is_sidebar_first_and_second= (empty($vars['page']['sidebar_first'])) &amp;&amp; (empty($vars['page']['sidebar_second']));
      if ($is_sidebar_first_or_second) {
        $vars['page']['content']['#theme_wrappers'][0] .= ' one-sidebar';
      }

      if ($is_sidebar_first_and_second) {
        $vars['page']['content']['#region'] .= ' two-sidebar';
      }

    }


can anyone help me on this?
Have you tried this code ?
I have taken it from here

// Add information about the number of sidebars.
  if (!empty($variables['page']['sidebar_first']) &amp;&amp; !empty($variables['page']['sidebar_second'])) {
    $variables['classes_array'][] = 'two-sidebars';
  }
  elseif (!empty($variables['page']['sidebar_first'])) {
    $variables['classes_array'][] = 'one-sidebar sidebar-first';
  }
  elseif (!empty($variables['page']['sidebar_second'])) {
    $variables['classes_array'][] = 'one-sidebar sidebar-second';
  }
  else {
    $variables['classes_array'][] = 'no-sidebars';
  }