Creating a Custom Theme

VitePress allows you to create completely custom themes to match your specific design requirements. A custom theme gives you full control over the layout, styling, and functionality of your documentation site.

Theme Structure

Theme Entry File

Create a theme entry file at .vitepress/theme/index.js or .vitepress/theme/index.ts:

.
├─ docs
│  ├─ .vitepress
│  │  ├─ theme
│  │  │  └─ index.js   # Theme entry
│  │  └─ config.js
│  └─ index.md
└─ package.json

When VitePress detects a theme entry file, it will use your custom theme instead of the default theme.

Theme Interface

A VitePress theme must implement this interface:

interface Theme {
  /**
   * Root layout component for every page
   * @required
   */
  Layout: Component
  
  /**
   * Enhance Vue app instance
   * @optional
   */
  enhanceApp?: (ctx: EnhanceAppContext) => Awaitable<void>
  
  /**
   * Extend another theme, calling its `enhanceApp` before ours
   * @optional
   */
  extends?: Theme
}

interface EnhanceAppContext {
  app: App // Vue app instance
  router: Router // VitePress router instance
  siteData: Ref<SiteData> // Site-level metadata
}

Basic Custom Theme

Minimal Setup

The simplest possible theme:

import Layout from './Layout.vue'

export default {
  Layout
}

The <Content /> component renders the compiled Markdown content.

With Type Safety

TypeScript
JSDoc

.vitepress/theme/index.ts

import type { Theme } from 'vitepress'
import Layout from './Layout.vue'

export default {
  Layout,
  enhanceApp({ app, router, siteData }) {
    // App enhancements
  }
} satisfies Theme

.vitepress/theme/index.js

import Layout from './Layout.vue'

/** @type {import('vitepress').Theme} */
export default {
  Layout,
  enhanceApp({ app, router, siteData }) {
    // App enhancements
  }
}

Building a Layout Component

Basic Layout

A layout needs at minimum the <Content /> component:

.vitepress/theme/Layout.vue

<script setup>
import { Content } from 'vitepress'
</script>

<template>
  <div class="layout">
    <header>
      <h1>My Site</h1>
    </header>
    
    <main>
      <Content />
    </main>
    
    <footer>
      <p>© 2024 My Company</p>
    </footer>
  </div>
</template>

<style scoped>
.layout {
  max-width: 1200px;
  margin: 0 auto;
  padding: 20px;
}
</style>

Handling 404 Pages

Use the useData() composable to detect 404 pages:

<script setup>
import { useData, Content } from 'vitepress'

const { page } = useData()
</script>

<template>
  <div class="layout">
    <div v-if="page.isNotFound" class="not-found">
      <h1>404</h1>
      <p>Page not found</p>
      <a href="/">Go home</a>
    </div>
    
    <Content v-else />
  </div>
</template>

Multiple Layout Types

Support different layouts via frontmatter:

<script setup>
import { useData, Content } from 'vitepress'
import HomePage from './HomePage.vue'
import DocPage from './DocPage.vue'
import NotFound from './NotFound.vue'

const { page, frontmatter } = useData()
</script>

<template>
  <NotFound v-if="page.isNotFound" />
  <HomePage v-else-if="frontmatter.layout === 'home'" />
  <DocPage v-else />
</template>

Then in your Markdown:

---
layout: home
---

# Home Page Content

Using Runtime Data

Available Composables

VitePress provides several composables for accessing runtime data:

useData
useRoute
useRouter

<script setup>
import { useData } from 'vitepress'

const { 
  site,        // Site-level data
  page,        // Current page data
  frontmatter, // Current page frontmatter
  params,      // Dynamic route params
  theme,       // Theme config
  isDark,      // Dark mode state
  lang,        // Current language
  localeIndex, // Current locale index
  title,       // Page title
  description  // Page description
} = useData()
</script>

<template>
  <div>
    <h1>{{ title }}</h1>
    <p>{{ description }}</p>
    <p>Theme: {{ isDark ? 'Dark' : 'Light' }}</p>
  </div>
</template>

<script setup>
import { useRoute } from 'vitepress'

const route = useRoute()
</script>

<template>
  <div>
    <p>Current path: {{ route.path }}</p>
    <p>Component: {{ route.component }}</p>
  </div>
</template>

<script setup>
import { useRouter } from 'vitepress'

const router = useRouter()

function goToPage() {
  router.go('/guide/')
}
</script>

<template>
  <button @click="goToPage">Go to Guide</button>
</template>

Accessing Page Data

<script setup>
import { useData } from 'vitepress'

const { page, frontmatter } = useData()
</script>

<template>
  <article>
    <h1>{{ page.title }}</h1>
    
    <div class="meta">
      <span v-if="frontmatter.author">By {{ frontmatter.author }}</span>
      <span v-if="frontmatter.date">{{ frontmatter.date }}</span>
      <span v-if="page.lastUpdated">
        Updated: {{ new Date(page.lastUpdated).toLocaleDateString() }}
      </span>
    </div>
    
    <Content />
  </article>
</template>

Enhancing the App

Registering Global Components

.vitepress/theme/index.js

import DefaultTheme from 'vitepress/theme'
import MyButton from './components/MyButton.vue'
import MyCard from './components/MyCard.vue'

export default {
  extends: DefaultTheme,
  enhanceApp({ app }) {
    app.component('MyButton', MyButton)
    app.component('MyCard', MyCard)
  }
}

Now use them in Markdown:

# My Page

<MyButton>Click me</MyButton>

<MyCard title="Card Title">
  Card content
</MyCard>

Auto-Registering Components

Use Vite’s glob import:

.vitepress/theme/index.js

import DefaultTheme from 'vitepress/theme'

export default {
  extends: DefaultTheme,
  enhanceApp({ app }) {
    // Auto-register all components from ./components
    const components = import.meta.glob('./components/**/*.vue', { eager: true })
    
    for (const path in components) {
      const component = components[path]
      const name = path.match(/\/([^\/]+)\.vue$/)?.[1]
      if (name) {
        app.component(name, component.default)
      }
    }
  }
}

Installing Vue Plugins

.vitepress/theme/index.js

import DefaultTheme from 'vitepress/theme'
import VueGtag from 'vue-gtag'

export default {
  extends: DefaultTheme,
  enhanceApp({ app, router }) {
    app.use(VueGtag, {
      config: { id: 'GA_MEASUREMENT_ID' }
    }, router)
  }
}

Adding Global State

.vitepress/theme/index.js

import { createPinia } from 'pinia'
import DefaultTheme from 'vitepress/theme'

export default {
  extends: DefaultTheme,
  enhanceApp({ app }) {
    const pinia = createPinia()
    app.use(pinia)
  }
}

SSR Compatibility

Your theme must be SSR-compatible. Avoid accessing browser-only APIs during SSR.

Conditional Browser Code

onMounted
ClientOnly Component
Dynamic Import

<script setup>
import { onMounted } from 'vue'

onMounted(() => {
  // Safe to use browser APIs here
  console.log(window.location.href)
  document.title = 'My Page'
})
</script>

<template>
  <ClientOnly>
    <BrowserOnlyComponent />
  </ClientOnly>
</template>

<script setup>
import { defineAsyncComponent } from 'vue'

const BrowserComponent = defineAsyncComponent(() =>
  import('./BrowserComponent.vue')
)
</script>

<template>
  <ClientOnly>
    <BrowserComponent />
  </ClientOnly>
</template>

Import Guards

if (typeof window !== 'undefined') {
  // Browser-only imports
  const analytics = await import('./analytics')
  analytics.init()
}

Theme Styling

Scoped Styles

<template>
  <div class="custom-layout">
    <Content />
  </div>
</template>

<style scoped>
.custom-layout {
  font-family: 'Inter', sans-serif;
  line-height: 1.6;
}
</style>

Global Styles

.vitepress/theme/index.js

import Layout from './Layout.vue'
import './styles/global.css'
import './styles/variables.css'

export default {
  Layout
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: system-ui, -apple-system, sans-serif;
}

code {
  font-family: 'Monaco', monospace;
  background: #f5f5f5;
  padding: 2px 6px;
  border-radius: 4px;
}

CSS Variables

:root {
  --color-primary: #3b82f6;
  --color-text: #1f2937;
  --color-background: #ffffff;
  --spacing-unit: 8px;
}

.dark {
  --color-text: #f9fafb;
  --color-background: #111827;
}

Distributing Your Theme

As npm Package

Structure your package:

my-vitepress-theme/
├─ src/
│  ├─ Layout.vue
│  ├─ index.ts
│  └─ components/
├─ package.json
└─ README.md

Export the theme:

src/index.ts

import type { Theme } from 'vitepress'
import Layout from './Layout.vue'

export type { ThemeConfig } from './config'

const theme: Theme = {
  Layout,
  enhanceApp({ app }) {
    // Theme enhancements
  }
}

export default theme

Package.json:

{
  "name": "my-vitepress-theme",
  "version": "1.0.0",
  "type": "module",
  "exports": {
    ".": "./src/index.ts",
    "./config": "./config.ts"
  },
  "files": ["src", "config.ts"],
  "peerDependencies": {
    "vitepress": "^1.0.0",
    "vue": "^3.0.0"
  }
}

Document usage:

README.md

# My VitePress Theme

## Installation

\`\`\`bash
npm install my-vitepress-theme
\`\`\`

## Usage

\`\`\`ts .vitepress/theme/index.ts
import Theme from 'my-vitepress-theme'

export default Theme
\`\`\`

## Configuration

\`\`\`ts .vitepress/config.ts
import { defineConfig } from 'vitepress'
import type { ThemeConfig } from 'my-vitepress-theme'

export default defineConfig<ThemeConfig>({
  themeConfig: {
    // Theme-specific options
  }
})
\`\`\`

As GitHub Template

Create a template repository with:

vitepress-theme-template/
├─ docs/
│  ├─ .vitepress/
│  │  ├─ theme/
│  │  │  ├─ Layout.vue
│  │  │  ├─ index.ts
│  │  │  └─ components/
│  │  └─ config.ts
│  └─ index.md
├─ package.json
└─ README.md

Users can then use “Use this template” to create their own repository.

Advanced Examples

Blog Theme

.vitepress/theme/Layout.vue

<script setup>
import { useData, useRoute } from 'vitepress'
import { data as posts } from './posts.data'

const { frontmatter, page } = useData()
const route = useRoute()

const isBlogPost = route.path.startsWith('/blog/')
</script>

<template>
  <div class="blog-layout">
    <header>
      <nav>
        <a href="/">Home</a>
        <a href="/blog/">Blog</a>
        <a href="/about/">About</a>
      </nav>
    </header>
    
    <main>
      <article v-if="isBlogPost" class="post">
        <h1>{{ page.title }}</h1>
        <div class="meta">
          <span>{{ frontmatter.author }}</span>
          <time>{{ frontmatter.date }}</time>
        </div>
        <Content />
      </article>
      
      <Content v-else />
    </main>
  </div>
</template>

.vitepress/theme/Layout.vue

<script setup>
import { useData } from 'vitepress'
import Sidebar from './Sidebar.vue'
import Navbar from './Navbar.vue'

const { theme, page } = useData()
</script>

<template>
  <div class="doc-layout">
    <Navbar />
    
    <div class="container">
      <Sidebar v-if="theme.sidebar" :items="theme.sidebar" />
      
      <main class="content">
        <article>
          <h1>{{ page.title }}</h1>
          <Content />
        </article>
      </main>
    </div>
  </div>
</template>

<style scoped>
.container {
  display: flex;
  max-width: 1400px;
  margin: 0 auto;
}

.content {
  flex: 1;
  padding: 2rem;
  max-width: 800px;
}
</style>

Complete Theme Example

.vitepress/theme/index.ts

import type { Theme } from 'vitepress'
import Layout from './Layout.vue'
import './styles/vars.css'
import './styles/base.css'

// Components
import Button from './components/Button.vue'
import Card from './components/Card.vue'
import Badge from './components/Badge.vue'

export interface ThemeConfig {
  navbar: {
    logo?: string
    items: NavItem[]
  }
  sidebar: SidebarConfig
  footer?: {
    message?: string
    copyright?: string
  }
}

const theme: Theme = {
  Layout,
  enhanceApp({ app, router, siteData }) {
    // Register global components
    app.component('Button', Button)
    app.component('Card', Card)
    app.component('Badge', Badge)
    
    // Add router hooks
    router.onBeforeRouteChange = (to) => {
      console.log('Navigating to', to)
    }
    
    // Global properties
    app.config.globalProperties.$myThemeVersion = '1.0.0'
  }
}

export default theme

Getting Started

Core Concepts

Customization

Advanced

​Creating a Custom Theme

​Theme Structure

​Theme Entry File

​Theme Interface

​Basic Custom Theme

​Minimal Setup

​With Type Safety

​Building a Layout Component

​Basic Layout

​Handling 404 Pages

​Multiple Layout Types

​Using Runtime Data

​Available Composables

​Accessing Page Data

​Enhancing the App

​Registering Global Components

​Auto-Registering Components

​Installing Vue Plugins

​Adding Global State

​SSR Compatibility

​Conditional Browser Code

​Import Guards

​Theme Styling

​Scoped Styles

​Global Styles

​CSS Variables

​Distributing Your Theme

​As npm Package

​As GitHub Template

​Advanced Examples

​Blog Theme

​Documentation Theme with Sidebar

​Complete Theme Example

​Next Steps

Extending Default Theme

Runtime API

Build docs developers (and LLMs) love

Creating a Custom Theme

Theme Structure

Theme Entry File

Theme Interface

Basic Custom Theme

Minimal Setup

With Type Safety

Building a Layout Component

Basic Layout

Handling 404 Pages

Multiple Layout Types

Using Runtime Data

Available Composables

Accessing Page Data

Enhancing the App

Registering Global Components

Auto-Registering Components

Installing Vue Plugins

Adding Global State

SSR Compatibility

Conditional Browser Code

Import Guards

Theme Styling

Scoped Styles

Global Styles

CSS Variables

Distributing Your Theme

As npm Package

As GitHub Template

Advanced Examples

Blog Theme

Documentation Theme with Sidebar

Complete Theme Example

Next Steps