MQtest.io — A simple tool to help identify which media queries your device responds to.
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Web Design réactif Article traduit de Seomoz.org : Responsive Web Design: The Ultimate Guide for Online Marketers http://www.seomoz.org/ugc/responsive-web-design-the-ultimate-guide-for-online-marketers
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A Beautiful Boilerplate for Responsive, Mobile-Friendly Development