The Wikimedia Design Style Guide provides a general design direction on the visual appearance and behaviour of a site and its user interface components. It is available as GitHub repository to enable low-hurdle contributions. It coexists with our main user interface library OOUI – have a look at its demos with its WikimediaUI theme and the developer documentation.
Contribute
Create a new ticket to discuss any proposal about the style guide, or check the existing ones.
For reports on user-interface issues for Wikimedia Foundation product, please see OOUI or UI-Standardization.