<div class="span12"></div>
to force 100% width. By default every block has 100% width.<div class="span6"></div>
<div class="span6"></div>
<div class="span4"></div>
<div class="span4"></div>
<div class="span4"></div>
<div class="span3"></div>
<div class="span3"></div>
<div class="span3"></div>
<div class="span3"></div>
<div class="span4"></div>
<div class="span8"></div>
<div class="span8"></div>
<div class="span4"></div>
<div class="span4"></div>
<div class="span4 offset4"></div>
<div class="span3 offset3"></div>
<div class="span3 offset3"></div>
<div class="span6 offset6"></div>
<div class="span6"></div>
<div class="span6"></div>