Board Thread:Support Requests - Designing Your Wiki/@comment-10183917-20130616220918/@comment-2200849-20130618173019

The titular "night chat" is a popular addition to Wikia chat, active on many wikis. Although local implementations may differ, the basic idea is that a button allows one to change the look and feel of the chat at the click of a button. This simply means that there's a day style and a night style, which only differ in terms of appearance and do not have any additional value, especially considering that a user switching to night chat won't automatically make the others switch to night chat as well. It's an amenity entirely for the end user.

This can be made by customizing Chat CSS and Javascript. Currently, this is a nontrivial, multi-step process, so I'd rather wait until you will be able to simply use MediaWiki:Chat.css and MediaWiki:Chat.js. The user-created pull request for this (https://github.com/Wikia/app/pull/838 ) was merged three days ago. The Technical Updates blog series will probably announce when it goes live.