It works! Congrats, you did it!

But after clicking around you realize that it does not anymore. Waaat? Maybe it's related to sidebar visibility changes? You open the inspector and see that .parent is {display:block}. Seems like some jQuery code assumed that display property is either `block` or `none`. Or something. Aaargh. The "sane" attribute of this solution was violated due to its non-locality to the `.rest`. Who could think that changing the display mode for the parent, which is indeed a private property of the parent, would lead to such an issue. You live and you learn css!

(Also, explanations for "intuitive" and/or "logical" are still missing.)