Change sidebar width w/o stretching widgets

Hello all.
Site: https://prheating.com/wordpress/
Theme: Tarnished – Modern Grunge

Ok, I was wondering if I could somehow resize the widgets pannel on the right so its skinnier without offsetting the widgets. When I edit the CSS to make it skinnier it just bumps the widgets over, and yes I have changed the padding. So I was wondering if anyone could take a look at it.