This is a CSS hack demonstration in which using an exploitable flaw in IE will allow web designers the option to display certain divs depending on if Internet Explorer is being used to view the page.
The way this works is that IE does not accept comments in CSS files using the double slash format, eg:
// display: hidden;
This enables us to prevent certain properties from being set in Firefox and other browsers but will always be set in IE, regardless of if you put double slashes before the property.
To test this, you should see a green box below if you are using IE, otherwise you should see a red box.
I discovered this trick while working on a layout and found that IE had set the border of a div in a totally different way than from what I saw in Firefox. If you're interested in how it works, just view the source code for this page as everything is there and easy to read.
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