--- id: using-themes title: Themes sidebar_label: Introduction --- Like plugins, themes are designed to add functionality to your Docusaurus site. As a good rule of thumb, themes are mostly focused on client-side, where plugins are more focused on server-side functionalities. Themes are also designed to be replace-able with other themes. ## Using themes To use themes, specify the themes in your `docusaurus.config.js`. You may use multiple themes: ```js {4} // docusaurus.config.js module.exports = { // ... themes: ['@docusaurus/theme-classic', '@docusaurus/theme-live-codeblock'], }; ``` ## Theme components Most of the time, theme is used to provide a set of React components, e.g. `Navbar`, `Layout`, `Footer`. Users can use these components in their code by importing them using the `@theme` webpack alias: ```js import Navbar from '@theme/Navbar'; ``` The alias `@theme` can refer to a few directories, in the following priority: 1. A user's `website/src/theme` directory, which is a special directory that has the higher precedence. 1. A Docusaurus theme packages's `theme` directory. 1. Fallback components provided by Docusaurus core (usually not needed). Given the following structure ``` website ├── node_modules │ └── docusaurus-theme │ └── theme │ └── Navbar.js └── src └── theme └── Navbar.js ``` `website/src/theme/Navbar.js` takes precedence whenever `@theme/Navbar` is imported. This behavior is called component swizzling. In iOS, method swizzling is the process of changing the implementation of an existing selector (method). In the context of a website, component swizzling means providing an alternative component that takes precedence over the component provided by the theme. **Themes are for providing UI components to present the content.** Most content plugins need to be paired with a theme in order to be actually useful. The UI is a separate layer from the data schema, so it makes it easy to swap out the themes for other designs (i.e., Bootstrap). For example, a Docusaurus blog consists of a blog plugin and a blog theme. ```js // docusaurus.config.js { theme: ['theme-blog'], plugins: ['plugin-content-blog'], } ``` and if you want to use Bootstrap styling, you can swap out the theme with `theme-blog-bootstrap` (fictitious non-existing theme): ```js // docusaurus.config.js { theme: ['theme-blog-bootstrap'], plugins: ['plugin-content-blog'], } ``` The content plugin remains the same and the only thing you need to change is the theme. ## Swizzling theme components > ⚠️ We would like to discourage swizzling of components until we've minimally reached a Beta stage. The components APIs have been changing rapidly and are likely to keep changing until we reach Beta. Stick with the default appearance for now if possible to save yourself some potential pain in future. Docusaurus Themes' components are designed to be replaceable. To make it easier for you, we created a command for you to replace theme components called `swizzle`. To swizzle a component for a theme, run the following command in your doc site: ```shell docusaurus swizzle [component name] ``` As an example, to swizzle the `