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Hi, I found a lot of information about responsive design and SEO, mostly theories no real experiment and I'd like to find a clear answer if someone tested that. Google says: 
Sites that use responsive web design, i.e. sites that serve all devices on the same set of URLs, with each URL serving the same HTML to all devices and using just CSS to change how the page is rendered on the device
https://developers.google.com/webmasters/smartphone-sites/details For usability reasons sometimes you need to hide content or links completely (not accessible at all by the visitor) on your page for small resolutions (mobile) using CSS ("visibility:hidden" or "display:none") Is this counted as hidden content and could penalize your site or not? What do you guys do when you create responsive design websites? Thanks! GaB