WordPress Jetpack Tiled images

I am wondering if/how to have my image gallery display across my full page width template?

Right now it seems to be using only about 60% of the page width. You can see it here:
https://www.wmis.org/2012-wmic-photo-gallery/

Is there something I can add to the css or short code to have it display the full page width while keeping the rectangular tiles?

Any help is appreciated.

Thanks!