Hi! :)
You can do that only if there is a close structural relationship between the two elements. I.e. the hidden element must be contained in the hovered element. Read link for all practical purposes since IEWin only supports :hover on links.
See Eric Meyers old demo here:
http://meyerweb.com/eric/css/edge/popups/demo.html
Also read this about the IE quirks. Got me tearing my hair out once, this one. :D
http://www.quirksmode.org/index.html...csspopups.html
If you want to turn arbitrary items all over the page on and off, you're better off with JavaScript.
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