Styling new widget areas

For a new widget area written like this:

<?php bfa_widget_area('name=Header Widget Area&cells=1&align=8&width_1=470'); ?>

How do I write the correct CSS insert to add margin-left:40px; ?

Basically, I don't want the widget ALL the way to the left (as set by align=8) and want to make some space on the left.