Board Thread:Support Requests - Getting Technical/@comment-39343160-20190503105456/@comment-9605025-20190506005343

As has already been stated, it is hard to help without access to the actual wiki. The reason is the MediaWiki has many different versions and flavors. Without knowing the exact versions you are using, no one here can give you a guaranteed detailed solution. The best we can do is draw on our experience from using Wikia's version and/or any other versions external to Wikia that we may have experience with.

As Fngplg said, you need to edit your wiki's CSS. That is about all we can guarantee to be accurate; everything else mentioned is based on assumptions of how your wiki works.