adding a left-margin to a custom sidebar

I’m sorry to bother with this, it’s not really a big problem but I’d like to add a left margin to a custom sidebar widget I added and I’m not sure exactly where to go since the plugin didn’t come with a stylesheet.

This is the site: http://berenicecurti.com.ar

The plugin is Custom Widget Area by Shakti Kumar. As you can see there’s no margin on the left of the slideshow. There wasn’t any to the left of the 4 column table either, I added it myself but I don’t know how to do the same to a slideshow.

I’d appreciate any ideas, thank you!