Multitheme

Multitheme is a design and software capability that allows a single product to present multiple visual styles or themes within a unified codebase. It enables users to select among predefined themes or switch automatically based on context, branding, or accessibility needs.

Used in web applications, content management systems, mobile apps, and desktop software, multitheme typically includes a theme engine, a set of theme definitions, and a mechanism for applying user-selected themes at runtime.

A theme definition usually comprises style tokens such as colors, typography, spacing, and component variants, alongside assets like logos and icons. Implementation often relies on CSS variables or tokens, themed templates, and asset pipelines.

Common implementation approaches include client-side runtime theming using a theme switch UI and storage of the chosen theme in cookies, local storage, or user profiles; and server-assisted theming that renders output in the selected theme.

Key design considerations include accessibility and contrast, responsive behavior, localization of type and imagery, performance and caching, and consistency across pages and components.

Benefits include flexible branding, improved user satisfaction, and the ability to support accessibility preferences. Challenges include increased maintenance, potential style drift, and ensuring theme compatibility with plugins and extensions.

Related concepts include dark mode and light mode variants, skinning and theming frameworks, and brand guidelines. Examples are typical web apps offering a light and dark theme as well as enterprise platforms that provide multiple brand-themed skins.