[Narutu]

Thee "pull-left" and "pull-right" classes were added into v2.2 (in the Github repository) in addition to the similar "float-left" and "float-right" classes.

These additions have been merged into the Master branch this afternoon.

The example site is running on v2.1 which uses the float-left and float-right classes.

Hope this helps.

[viciousambition]

I think (s)he means they're not present in the sample code under "pull-left & pull-right". The code block's divs just have column and size classes.

[Narutu]

Great spot. I apologise to the original commenter, the classes were indeed missing.