There are almost 300 comments here and no one has pointed out the obvious: these can be used within email templates where JavaScript is unavailable. For that re

There are almost 300 comments here and no one has pointed out the obvious: these can be used within email templates where JavaScript is unavailable. For that reason alone, I think this is pretty cool. But sure. Always use the right tool for the job, as they say, and for application logic that tool is not CSS.