diff --git a/horizontal-tabs/horizontal-tabs.js b/horizontal-tabs/horizontal-tabs.js
index c2ab3ee..aacecb0 100755
--- a/horizontal-tabs/horizontal-tabs.js
+++ b/horizontal-tabs/horizontal-tabs.js
@@ -34,6 +34,13 @@ Drupal.behaviors.horizontalTabs = {
           fieldset: $(this)
         });
         horizontal_tab.item.addClass('horizontal-tab-button-' + i);
+        
+        // Extract group name and add as class to button.
+        var id = $($fieldsets.get(i)).attr('id');
+        var offset = id.indexOf('group');
+        var field_name = id.substring(offset, id.length);
+        horizontal_tab.item.addClass(field_name);
+        
         tab_list.append(horizontal_tab.item);
         $(this)
           .removeClass('collapsible collapsed')