Examples
Default styling
.primary
Drupal's default tab markup styling.
Markup
<ul class="primary">
<li><a href="#">Tab 1</a></li>
<li class="active"><a href="#" class="active">Tab 1</a></li>
<li><a href="#">Tab 1</a></li>
</ul>
Source:
frontpack/drupal/drupal7/components/_tabs.scss, line 1