Discourse is a forum platform that’s built to be simple, accessible and powerful.
Discourse is 100% free and open-source. The platform’s chief goal is changing the way discussion boards and mailing lists look like in the year 2013.
Among the many innovative features are AJAX-powered thread browsing, automatically expanding links, replying with new topics and so on. Discourse runs on Ember.js; the server side is Ruby and Postgresql.
xy.css is a template for a design based on responsive grids.
xy.css is impeccably designed and offers the following features among others:
A combination of a vertical & horizontal grid
The website itself is designed with WP, HTML5 and xy.css; it very much showcases the use of this neat little library, and as if that’s not enough, it also features an extensive documentation of this interesting CSS template.