Extending the Default Theme

The VitePress default theme is highly customizable through CSS variables, component registration, and layout slots. This allows you to build on top of the default theme without creating a theme from scratch.

Before proceeding, make sure you understand how custom themes work.

Basic Setup

Theme Entry File

Create .vitepress/theme/index.js or .vitepress/theme/index.ts:

import type { Theme } from 'vitepress'
import DefaultTheme from 'vitepress/theme'
import './custom.css'

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

Customizing CSS

CSS Variables

The default theme uses CSS custom properties for styling. Override them to customize colors, fonts, spacing, and more.

Colors
Typography
Layout
Components

.vitepress/theme/custom.css

:root {
  /* Brand colors */
  --vp-c-brand-1: #646cff;
  --vp-c-brand-2: #747bff;
  --vp-c-brand-3: #535bf2;
  
  /* Background colors */
  --vp-c-bg: #ffffff;
  --vp-c-bg-alt: #f6f6f7;
  --vp-c-bg-elv: #ffffff;
  --vp-c-bg-soft: #f6f6f7;
}

.dark {
  --vp-c-bg: #1b1b1f;
  --vp-c-bg-alt: #161618;
  --vp-c-bg-elv: #202127;
  --vp-c-bg-soft: #202127;
}

.vitepress/theme/custom.css

:root {
  /* Font families */
  --vp-font-family-base: 'Inter', system-ui, sans-serif;
  --vp-font-family-mono: 'Monaco', monospace;
  
  /* Font sizes */
  --vp-font-size-base: 16px;
  --vp-font-size-small: 14px;
  --vp-font-size-large: 18px;
  
  /* Line heights */
  --vp-line-height-base: 1.7;
  --vp-line-height-heading: 1.2;
}

.vitepress/theme/custom.css

:root {
  /* Layout dimensions */
  --vp-layout-max-width: 1440px;
  --vp-sidebar-width-small: 272px;
  --vp-sidebar-width-mobile: 320px;
  
  /* Spacing */
  --vp-spacing-sm: 8px;
  --vp-spacing-md: 16px;
  --vp-spacing-lg: 24px;
  --vp-spacing-xl: 32px;
}

.vitepress/theme/custom.css

:root {
  /* Buttons */
  --vp-button-brand-bg: var(--vp-c-brand-1);
  --vp-button-brand-hover-bg: var(--vp-c-brand-2);
  
  /* Code blocks */
  --vp-code-font-size: 14px;
  --vp-code-line-height: 1.5;
  --vp-code-block-bg: #f6f6f7;
  
  /* Links */
  --vp-c-link: var(--vp-c-brand-1);
  --vp-c-link-hover: var(--vp-c-brand-2);
}

See the full list of CSS variables in the VitePress source code.

Custom Styles

Add custom CSS rules:

.vitepress/theme/custom.css

/* Custom heading styles */
.vp-doc h1 {
  border-bottom: 2px solid var(--vp-c-brand-1);
  padding-bottom: 0.5rem;
}

/* Custom link styles */
.vp-doc a {
  text-decoration: underline;
  text-underline-offset: 4px;
}

/* Custom code block styles */
.vp-doc div[class*='language-'] {
  border-radius: 8px;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

/* Custom sidebar styles */
.VPSidebar {
  background: linear-gradient(180deg, 
    var(--vp-c-bg) 0%, 
    var(--vp-c-bg-soft) 100%
  );
}

Using Custom Fonts

Web Fonts

By default, VitePress includes Inter font. To use different fonts:

.vitepress/theme/index.js

import DefaultTheme from 'vitepress/theme-without-fonts'
import './fonts.css'

export default DefaultTheme

.vitepress/theme/fonts.css

@import url('https://fonts.googleapis.com/css2?family=Roboto:wght@400;500;700&display=swap');

:root {
  --vp-font-family-base: 'Roboto', sans-serif;
}

Import from vitepress/theme-without-fonts to avoid bundling the default Inter font.

Local Fonts

.vitepress/theme/fonts.css

@font-face {
  font-family: 'CustomFont';
  src: url('./assets/custom-font.woff2') format('woff2');
  font-weight: normal;
  font-style: normal;
  font-display: swap;
}

:root {
  --vp-font-family-base: 'CustomFont', sans-serif;
}

Preload the font:

.vitepress/config.ts

export default defineConfig({
  transformHead({ assets }) {
    const fontFile = assets.find(file => /custom-font\.\w+\.woff2/.test(file))
    if (fontFile) {
      return [
        [
          'link',
          {
            rel: 'preload',
            href: fontFile,
            as: 'font',
            type: 'font/woff2',
            crossorigin: ''
          }
        ]
      ]
    }
  }
})

Registering Components

Global Components

Single Component
Multiple Components
Auto-Register

.vitepress/theme/index.js

import DefaultTheme from 'vitepress/theme'
import MyComponent from './components/MyComponent.vue'

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

.vitepress/theme/index.js

import DefaultTheme from 'vitepress/theme'
import Button from './components/Button.vue'
import Card from './components/Card.vue'
import Badge from './components/Badge.vue'

export default {
  extends: DefaultTheme,
  enhanceApp({ app }) {
    app.component('Button', Button)
    app.component('Card', Card)
    app.component('Badge', Badge)
  }
}

.vitepress/theme/index.js

import DefaultTheme from 'vitepress/theme'

export default {
  extends: DefaultTheme,
  enhanceApp({ app }) {
    // Auto-register all 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)
      }
    }
  }
}

Layout Slots

The default theme provides layout slots to inject custom content at specific locations.

Available Slots

Doc Layout
Home Layout
Page Layout
Global Slots

When layout: 'doc' (default):

doc-top - Before doc content
doc-bottom - After doc content
doc-footer-before - Before doc footer
doc-before - Before doc container
doc-after - After doc container
sidebar-nav-before - Before sidebar nav
sidebar-nav-after - After sidebar nav
aside-top - Top of aside
aside-bottom - Bottom of aside
aside-outline-before - Before outline
aside-outline-after - After outline
aside-ads-before - Before ads
aside-ads-after - After ads

When layout: 'home':

home-hero-before - Before hero section
home-hero-info-before - Before hero info
home-hero-info - Hero info
home-hero-info-after - After hero info
home-hero-actions-after - After hero actions
home-hero-image - Hero image
home-hero-after - After hero
home-features-before - Before features
home-features-after - After features

When layout: 'page':

page-top - Top of page
page-bottom - Bottom of page

Always available:

layout-top - Top of layout
layout-bottom - Bottom of layout
nav-bar-title-before - Before nav title
nav-bar-title-after - After nav title
nav-bar-content-before - Before nav content
nav-bar-content-after - After nav content
nav-screen-content-before - Before mobile nav
nav-screen-content-after - After mobile nav
not-found - 404 page

Using Slots with Components

With Layout Wrapper
With Render Function

.vitepress/theme/index.js

import DefaultTheme from 'vitepress/theme'
import MyLayout from './MyLayout.vue'

export default {
  extends: DefaultTheme,
  Layout: MyLayout
}

.vitepress/theme/MyLayout.vue

<script setup>
import DefaultTheme from 'vitepress/theme'
import CustomSidebar from './CustomSidebar.vue'
import Banner from './Banner.vue'

const { Layout } = DefaultTheme
</script>

<template>
  <Layout>
    <template #doc-top>
      <Banner />
    </template>
    
    <template #sidebar-nav-before>
      <CustomSidebar />
    </template>
    
    <template #aside-outline-after>
      <div class="custom-toc-footer">
        <a href="#">Back to top</a>
      </div>
    </template>
  </Layout>
</template>

.vitepress/theme/index.js

import { h } from 'vue'
import DefaultTheme from 'vitepress/theme'
import Banner from './components/Banner.vue'
import TableOfContents from './components/TableOfContents.vue'

export default {
  extends: DefaultTheme,
  Layout() {
    return h(DefaultTheme.Layout, null, {
      'doc-top': () => h(Banner),
      'aside-outline-before': () => h(TableOfContents)
    })
  }
}

Slot Examples

.vitepress/theme/MyLayout.vue

<script setup>
import DefaultTheme from 'vitepress/theme'
const { Layout } = DefaultTheme
</script>

<template>
  <Layout>
    <template #doc-top>
      <div class="banner">
        <p>📢 This is a beta version. <a href="/feedback">Give feedback</a></p>
      </div>
    </template>
  </Layout>
</template>

<style scoped>
.banner {
  background: var(--vp-c-brand-soft);
  padding: 12px 24px;
  text-align: center;
  border-radius: 8px;
  margin-bottom: 24px;
}
</style>

Add Contributors List

.vitepress/theme/MyLayout.vue

<script setup>
import { useData } from 'vitepress'
import DefaultTheme from 'vitepress/theme'
import Contributors from './Contributors.vue'

const { Layout } = DefaultTheme
const { frontmatter } = useData()
</script>

<template>
  <Layout>
    <template #doc-after>
      <Contributors 
        v-if="frontmatter.contributors" 
        :contributors="frontmatter.contributors" 
      />
    </template>
  </Layout>
</template>

.vitepress/theme/MyLayout.vue

<script setup>
import DefaultTheme from 'vitepress/theme'
const { Layout } = DefaultTheme
</script>

<template>
  <Layout>
    <template #sidebar-nav-after>
      <div class="sidebar-footer">
        <h3>Need Help?</h3>
        <ul>
          <li><a href="/support">Support</a></li>
          <li><a href="/discord">Discord</a></li>
          <li><a href="/github">GitHub</a></li>
        </ul>
      </div>
    </template>
  </Layout>
</template>

<style scoped>
.sidebar-footer {
  padding: 16px;
  border-top: 1px solid var(--vp-c-divider);
  margin-top: 16px;
}
</style>

Overriding Components

Replace default theme components using Vite aliases:

.vitepress/config.ts

import { fileURLToPath, URL } from 'node:url'
import { defineConfig } from 'vitepress'

export default defineConfig({
  vite: {
    resolve: {
      alias: [
        {
          find: /^.*\/VPNavBar\.vue$/,
          replacement: fileURLToPath(
            new URL('./theme/components/CustomNavBar.vue', import.meta.url)
          )
        },
        {
          find: /^.*\/VPFooter\.vue$/,
          replacement: fileURLToPath(
            new URL('./theme/components/CustomFooter.vue', import.meta.url)
          )
        }
      ]
    }
  }
})

Component names may change between minor releases. Check the source code for current names.

View Transitions

On Appearance Toggle

Add smooth transitions when toggling dark mode:

.vitepress/theme/Layout.vue

<script setup lang="ts">
import { useData } from 'vitepress'
import DefaultTheme from 'vitepress/theme'
import { nextTick, provide } from 'vue'

const { isDark } = useData()

const enableTransitions = () =>
  'startViewTransition' in document &&
  window.matchMedia('(prefers-reduced-motion: no-preference)').matches

provide('toggle-appearance', async ({ clientX: x, clientY: y }: MouseEvent) => {
  if (!enableTransitions()) {
    isDark.value = !isDark.value
    return
  }

  const clipPath = [
    `circle(0px at ${x}px ${y}px)`,
    `circle(${Math.hypot(
      Math.max(x, innerWidth - x),
      Math.max(y, innerHeight - y)
    )}px at ${x}px ${y}px)`
  ]

  await document.startViewTransition(async () => {
    isDark.value = !isDark.value
    await nextTick()
  }).ready

  document.documentElement.animate(
    { clipPath: isDark.value ? clipPath.reverse() : clipPath },
    {
      duration: 300,
      easing: 'ease-in',
      pseudoElement: `::view-transition-${isDark.value ? 'old' : 'new'}(root)`
    }
  )
})
</script>

<template>
  <DefaultTheme.Layout />
</template>

<style>
::view-transition-old(root),
::view-transition-new(root) {
  animation: none;
  mix-blend-mode: normal;
}

::view-transition-old(root),
.dark::view-transition-new(root) {
  z-index: 1;
}

::view-transition-new(root),
.dark::view-transition-old(root) {
  z-index: 9999;
}
</style>

Complete Example

.vitepress/theme/index.js

import { h } from 'vue'
import type { Theme } from 'vitepress'
import DefaultTheme from 'vitepress/theme'

// Custom CSS
import './custom.css'
import './fonts.css'

// Custom components
import Banner from './components/Banner.vue'
import Contributors from './components/Contributors.vue'
import CustomButton from './components/CustomButton.vue'
import Analytics from './components/Analytics.vue'

export default {
  extends: DefaultTheme,
  
  Layout() {
    return h(DefaultTheme.Layout, null, {
      'doc-top': () => h(Banner),
      'doc-after': () => h(Contributors),
      'layout-bottom': () => h(Analytics)
    })
  },
  
  enhanceApp({ app, router, siteData }) {
    // Register global components
    app.component('CustomButton', CustomButton)
    
    // Add router hooks
    router.onAfterRouteChanged = (to) => {
      // Track page views
      if (typeof window !== 'undefined' && window.gtag) {
        window.gtag('event', 'page_view', {
          page_path: to
        })
      }
    }
    
    // Global error handler
    app.config.errorHandler = (err, instance, info) => {
      console.error('App error:', err, info)
    }
  }
} satisfies Theme

Getting Started

Core Concepts

Customization

Advanced

Extending the Default Theme

Extending the Default Theme

Basic Setup

Theme Entry File

Customizing CSS

CSS Variables

Custom Styles

Using Custom Fonts

Web Fonts

Local Fonts

Registering Components

Global Components

Layout Slots

Available Slots

Using Slots with Components

Slot Examples

Add Banner to All Docs

Add Contributors List

Custom Sidebar Footer

Overriding Components

View Transitions

On Appearance Toggle

Complete Example

Next Steps

Theme Configuration

Custom Theme

Build docs developers (and LLMs) love

Getting Started

Core Concepts

Customization

Advanced

​Extending the Default Theme

​Basic Setup

​Theme Entry File

​Customizing CSS

​CSS Variables

​Custom Styles

​Using Custom Fonts

​Web Fonts

​Local Fonts

​Registering Components

​Global Components

​Layout Slots

​Available Slots

​Using Slots with Components

​Slot Examples

​Add Banner to All Docs

​Add Contributors List

​Custom Sidebar Footer

​Overriding Components

​View Transitions

​On Appearance Toggle

​Complete Example

​Next Steps

Theme Configuration

Custom Theme

Build docs developers (and LLMs) love

Extending the Default Theme

Basic Setup

Theme Entry File

Customizing CSS

CSS Variables

Custom Styles

Using Custom Fonts

Web Fonts

Local Fonts

Registering Components

Global Components

Layout Slots

Available Slots

Using Slots with Components

Slot Examples

Add Banner to All Docs

Add Contributors List

Custom Sidebar Footer

Overriding Components

View Transitions

On Appearance Toggle

Complete Example

Next Steps