## Description

[Reactive controllers](https://lit.dev/docs/composition/controllers/) are a tool for code reuse and composition within [Lit](https://lit.dev), a core dependency of Spectrum Web Components. Reactive controllers can be reused across components to reduce both code complexity and size, and to deliver a consistent user experience. These reactive controllers are used by the Spectrum Web Components library and are published to NPM for you to leverage in your projects as well.

### Reactive controllers

-   [ColorController](../color-controller)
-   [ElementResolutionController](../element-resolution)
-   FocusGroupController
-   LanguageResolutionController
-   [MatchMediaController](../match-media)
-   [RovingTabindexController](../roving-tab-index)
-   [PendingStateController](../pending-state)
-   SystemContextResolutionController