You can try with changing page content padding by going to single page -> edit and find Agama Options metabox and from Page Options (Tab) -> Page Content Padding you can set bottom padding to “0px”.
Cannot access to website… i think that extra space is there only when you are logged-in as administrator since edit button is there… try logout from website and refresh page.
As soon as I change the color of the buttons to #067790 instead of the pink color, the articles get in 1 column instead of 3… This seems to be a bug I could not resolve yesterday.