Theme messed up

I have no idea what has happened to the theme, but I tried to install this widget – http://wordpress.org/extend/plugins/facebook-like-box/.

It messed up my layout so I uninstalled it, but I still do not understand what has happened?

Please have a look – http://www.echofestival.com

The original theme – http://themeforest.net/item/bonsai-minimalist-wordpress-theme/full_screen_preview/238277