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Should the administration section of a website have the same look & feel as the other parts of the website?
I'm building a SAAS application and all of the public-facing parts of the website (home page, blog, about us, etc) share a HTML/CSS look & feel. I now need to add HTML/CSS to the admin section of the website (the bit that someone gets access to once they have signed up so that they can configure the SAAS options). Should the admin section share the same look & feel as the website proper? Is there any reason not to have a completely difference layout and colour scheme? Is it better to keep the same look so that users know they are still in the application or have a different look to differentiate the admin from the public-facing pages?