Typo on getbem's CSS

[andres039]

I'm new to web development and maybe that's why I couldn't find your stylesheets on github, but there's a typo in line 586 of your http://getbem.com/getbem.com.1.0.0.css document. I was trying to figure out why the examples under the class .introduction__cell--block are asymetrical with respect to the other examples. Well, thank you, I 'm not trying to be arrogant but just helpful trying to give a hand with some details. Cheers!