Prefix the new Theme classes. Fixes #25966

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Themes: For small screen sizes, still allow access to the Customize button (Don't hide the theme actions). See #25948

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git-svn-id: http://core.svn.wordpress.org/trunk@26390 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Add the proper padding-top for button's active states in small screens. Fixes #26346

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git-svn-id: http://core.svn.wordpress.org/trunk@26391 1a063a9b-81f0-0310-95a4-ce76da25c4cd
Themes: In the detailed view, disable the next/previous buttons when there are no more items. Fixes #26314

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