<div class="col-sm-3 col-xs-12">
    <?php $sidebar_pos=apply_filters('st_blog_sidebar','right');
    if($sidebar_pos=="left"){
        echo "<aside class='sidebar-left'>";
    }elseif($sidebar_pos=="right"){
        echo "<aside class='sidebar-right'>";
    }
    ?>
    <?php dynamic_sidebar(apply_filters('st_blog_sidebar_id','blog-sidebar')); ?>
    </aside>
</div>