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    A behavior for Internet Explorer allowing it to recognize and render various CSS3 box decoration properties
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                                         ======      PIE       ======
                                                 Mmmmmm, pie.

    CSS Level 3 brings with it some incredibly powerful styling features. Rounded corners, soft drop shadows, gradient fills, and so on. These are the kinds of elements our designer friends love to use because they make for attractive sites, but are difficult and time-consuming to implement, involving complex sprite images, extra non-semantic markup, large JavaScript libraries, and other lovely hacks.

    CSS3 promises to do away with all that! But as we all know, due to Internet Explorer's lack of support for any of these features, we must be patient and refrain from using them, and make do with the same old tedious techniques for the foreseeable future.

    Or must we?

    PIE stands for Progressive Internet Explorer. It is an IE attached behavior which, when applied to an element, allows IE to recognize and display a number of CSS3 properties. Consider, if you will, the following CSS:

    #myElement {
        background: #EEE;
        padding: 2em;
        -moz-border-radius: 1em;
        -webkit-border-radius: 1em;
        border-radius: 1em;

    This results in a box with nicely rounded corners in any of today's modern browsers, except of course for IE 6, 7, or 8, which all display a square box. However, add the following single rule to that CSS:

    #myElement {
        behavior: url(;

    Now the exact same rounded corners appear in IE! That's all there is to it. No, really, I mean it.

    PIE currently has full or partial support for the following CSS3 features:

    * border-radius
    * box-shadow
    * border-image
    * multiple background images
    * linear-gradient as background image

    Other features such as radial gradients, multiple box shadows, and many many bugfixes are under development. This is still a young project which has a long way to go, but is already pretty remarkable! We're working on getting a site up with documentation and examples. Contributions (code, documentation, testing) are greatly appreciated!

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