The Pack lets Illustrator users create HTML5 illustrations equipped with CSS3, Canvas Tags and more. This is quite a significant move, the introduction of the Illustrator CS5 HTML5 Pack . The move breaks the cycle slightly, enabling Web designers to grab back a little control over their creations from those eponymous ‘Web developers’. In combination with the HTML5 features available in the Adobe Dreamweaver CS5 11.0.3 updater, these new tools allow web designers to take advantage of the latest advancements in HTML5. Features (from Adobe’s Web site):

Efficiently design for web and devices by exporting Illustrator Artboards for unique screen sizes using SVG and CSS3 media queries. Create web widgets with Illustrator by generating dynamic vector art for data driven web work-flows. Take advantage of the latest enhancements to SVG and Canvas to generate interactive web content. Map artwork appearance attributes from designer to developer tools—export from the Illustrator Appearance Panel to CSS3 for streamlined styling of web pages.

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