How to eliminate empty space

Here’s a link to my WordPress site:

https://www.schoollifetroy.com

I like the Responsive theme because it works beautifully on mobile devices as well as on a computer.

QUESTION:
How can I eliminate the empty space between the Home Widgets and the Colophon Widget?

DETAILS:
The Home Widgets are the three vertical white boxes, and the Colophon Widget is the text area with a thin white border at the bottom of the page. There’s a 1″ horizontal gap between them which I would love to eliminate (or fill with something).

Any suggestions would be greatly appreciated!
–Ed