CSS generated content is not only the best way for clearfixes, it is also especially helpful if you want to create visually impressive objects with a minimal amount of markup. Due to a long existing bug in Webkit (3 years!) pseudo elements like :before and :after cannot be animated via transitions, yet.
But there is a way to fix this issue, as Roman Komarov presented at the Jam Session at Fronteers Conf this year. And a usually disregarded property value enters the stage for this work around.
