Is there anybody here at all that knows about MediaWIki? Perhaps I have been posting in the wrong thread.
I have found a few codes that I have put in "MediaWiki:Common.css" From what I understand, this customizes ALL skins and as a result,
users can select own skin from an option of available skins once they create and log in. and I can keep the same theme across all skins. (Headers are Dark red with white text.)
With MediaWiki:Common.css I have been able to change the appearance of the headers, and also change the colors of the words "navigation", "search", "toolbars" on the sidebar.
I have also added links to Navigation. But I edited the article "MediaWiki:Sidebar".
Will Editing "The MediaWiki:Sidebar" change ALL the skins?
Or do I have to edit "MediaWiki:Common.css"? If so, how? And are there any others that I should edit that I don't know about?
If None Of This Is Possible,
Should I just get rid of all those other skins and focus on editing just one skin?
Which of these two options is easier?

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