Board Thread:Support Requests - Designing Your Wiki/@comment-31184975-20181114141844/@comment-9605025-20181114200750

That wiki uses a separate stylesheet for their portable infobox themes. You can find it at MediaWiki:Themes.css. The first thing you can try is [ exporting Themes.css] ([ with page history]) (help page) from that wiki and then import it to yours. Don't forget to import the stylesheet in MediaWiki:Wikia.css (help page) similar to how they did it.