How to Change Size of Text Boxes in Forms

Hi,

I installed the Barlow them and I love it for a small blog site. The only issue I'm having is that all the text boxes, for example, the name and email entry boxes in the "contact" form, and the username box in the "login" form, are too long. Do you know of an easy way to make these shorter from within the theme, e.g., by editing one of the css or php files? They currently are set at 60 characters, and I would prefer something like 30.

Thanks for any insight.

Neil