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Css can't actually do that in the way you want it to. Javascript, like this example, can.
Due to how rows of floated or inline-blocked content behave, css isn't right for the job. You'd have to dynamically generate vertical columns of content and place them side by side, meaning you'd have to fight to get current content at the top. It would be kind of a pain, really. You'd also lose the responsiveness to window width.