Nuxt/docs/1.getting-started/4.styling.md
2023-06-18 21:28:03 +01:00

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---
navigation.icon: uil:palette
---
# Styling
Nuxt is highly flexible when it comes to styling. Write your own styles, or reference local and external stylesheets.
You can use CSS preprocessors, CSS frameworks, UI libraries and Nuxt modules to style your application.
## Local Stylesheets
If you're writing local stylesheets, the natural place to put them is the `assets/` directory.
### Importing Within Components
You can import stylesheets in your pages, layouts and components directly.
You can use a javascript import, or a css [`@import` statement](https://developer.mozilla.org/en-US/docs/Web/CSS/@import).
```vue [pages/index.vue]
<script>
import '~/assets/css/first.css'
</script>
<style>
@import url("~/assets/css/second.css");
</style>
```
::alert{type=info}
The stylesheets will be inlined in the HTML rendered by Nuxt.
::
### The CSS Property
You can also use the `css` property in the Nuxt configuration.
The natural place for your stylesheets is the `assets/` directory. You can then reference its path and Nuxt will include it to all the pages of your application.
```ts [nuxt.config.ts]
export default defineNuxtConfig({
css: ['~/assets/css/main.css']
})
```
::alert{type=info}
The stylesheets will be inlined in the HTML rendered by Nuxt, injected globally and present in all pages.
::
### Working With Fonts
Place your local fonts files in your `~/public/` directory, for example in `~/public/fonts`. You can then reference them in your stylesheets using `url()`.
```css [assets/css/main.css]
@font-face {
font-family: 'FarAwayGalaxy';
src: url('/fonts/FarAwayGalaxy.woff') format('woff');
font-weight: normal;
font-style: normal;
font-display: swap;
}
```
Then reference your fonts by name in your stylesheets, pages or components:
```vue
<style>
h1 {
font-family: 'FarAwayGalaxy', sans-serif;
}
</style>
```
### Stylesheets Distributed Through NPM
You can also reference stylesheets that are distributed through npm. Let's use the popular `animate.css` library as an example.
```bash
npm install animate.css
```
Then you can reference it directly in your pages, layouts and components:
```vue [app.vue]
<script>
import 'animate.css'
</script>
<style>
@import url("animate.css");
</style>
```
The package can also be referenced as a string in the css property of your Nuxt configuration.
```ts [nuxt.config.ts]
export default defineNuxtConfig({
css: ['animate.css']
})
```
## External Stylesheets
You can include external stylesheets in your application by adding a link element in the head section of your nuxt.config file. You can achieve this result using different methods. Note that local stylesheets can also be included like this.
You can manipulate the head with the `app.head` property of your Nuxt configuration:
```ts [nuxt.config.ts]
export default defineNuxtConfig({
app: {
head: {
link: [{ rel: 'stylesheet', href: 'https://cdnjs.cloudflare.com/ajax/libs/animate.css/4.1.1/animate.min.css' }]
}
}})
```
### Dynamically Adding Stylesheets
You can use the useHead composable to dynamically set a value in your head in your code.
::ReadMore{link="/docs/api/composables/use-head"}
::
```ts
useHead({
link: [{ rel: 'stylesheet', href: 'https://cdnjs.cloudflare.com/ajax/libs/animate.css/4.1.1/animate.min.css' }]
})
```
Nuxt uses `unhead` under the hood, and you can refer to its full documentation [here](https://unhead.harlanzw.com/).
### Modifying The Rendered Head With A Nitro Plugin
If you need more advanced control, you can intercept the rendered html with a hook and modify the head programmatically.
Create a plugin in `~/server/plugins/my-plugin.ts` like this:
```ts [server/plugins/my-plugin.ts]
export default defineNitroPlugin((nitro) => {
nitro.hooks.hook('render:html', (html) => {
html.head.push('<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/animate.css/4.1.1/animate.min.css">')
})
})
```
External stylesheets are render-blocking resources: they must be loaded and processed before the browser renders the page. Web pages that contain unnecessarily large styles take longer to render. You can read more about it on [web.dev](https://web.dev/defer-non-critical-css/).
## Using Preprocessors
To use a preprocessor like SCSS, Sass, Less or Stylus, install it first.
::code-group
```bash [Sass & SCSS]
npm install sass
```
```bash [Less]
npm install less
```
```bash [Stylus]
npm install stylus
```
::
The natural place to write your stylesheets is the `assets` directory.
You can then import your source files in your `app.vue` (or layouts files) using your preprocessor's syntax.
```vue [pages/app.vue]
<style lang="scss">
@use "~/assets/scss/main.scss";
</style>
```
Alternatively, you can use the `css` property of your Nuxt configuration.
```ts [nuxt.config.ts]
export default defineNuxtConfig({
css: ['~/assets/scss/main.scss']
})
```
::alert{type=info}
In both cases, the compiled stylesheets will be inlined in the HTML rendered by Nuxt.
::
If you need to inject code in pre-processed files, like a [sass partial](https://sass-lang.com/documentation/at-rules/use#partials) with color variables, you can do so with the vite [preprocessors options](https://vitejs.dev/config/shared-options.html#css-preprocessoroptions).
Create some partials in your `assets` directory:
::code-group
```scss [assets/_colors.scss]
$primary: #49240F;
$secondary: #E4A79D;
```
```sass [assets/_colors.sass]
$primary: #49240F
$secondary: #E4A79D
```
::
Then in your `nuxt.config` :
::code-group
```ts [SCSS]
export default defineNuxtConfig({
vite: {
css: {
preprocessorOptions: {
scss: {
additionalData: '@use "@/assets/_colors.scss" as *;'
}
}
}
}
})
```
```ts [SASS]
export default defineNuxtConfig({
vite: {
css: {
preprocessorOptions: {
sass: {
additionalData: '@use "@/assets/_colors.sass" as *\n'
}
}
}
}
})
```
::
Nuxt uses Vite by default. If you wish to use webpack instead, refer to each preprocessor loader [documentation](https://webpack.js.org/loaders/sass-loader/).
## Single File Components (SFC) Styling
One of the best thing about Vue and SFC is how great it is at naturally dealing with styling. You can directly write CSS or preprocessor code in the style block of your components file, therefore you will have fantastic developer experience without having to use something like CSS-in-JS. However if you wish to use CSS-in-JS, you can find 3rd party libraries and modules that support it, such as [pinceau](https://pinceau.dev/).
You can refer to the [Vue docs](https://vuejs.org/api/sfc-css-features.html) for a comprehensive reference about styling components in SFC.
### Class And Style Bindings
You can leverage Vue SFC features to style your components with class and style attributes.
::code-group
```vue [Ref and Reactive]
<script setup>
const isActive = ref(true)
const hasError = ref(false)
const classObject = reactive({
active: true,
'text-danger': false
})
</script>
<div class="static" :class="{ active: isActive, 'text-danger': hasError }"></div>
<div :class="classObject"></div>
```
```vue [Computed]
<script setup>
const isActive = ref(true)
const error = ref(null)
const classObject = computed(() => ({
active: isActive.value && !error.value,
'text-danger': error.value && error.value.type === 'fatal'
}))
</script>
<template>
<div :class="classObject"></div>
</template>
```
```vue [Array]
<script setup>
const isActive = ref(true)
const errorClass = ref('text-danger')
</script>
<template>
<div :class="[{ active: isActive }, errorClass]"></div>
</template>
```
```vue [Style]
<script setup>
const activeColor = ref('red')
const fontSize = ref(30)
const styleObject = reactive({ color: 'red', fontSize: '13px' })
</script>
<template>
<div :style="{ color: activeColor, fontSize: fontSize + 'px' }"></div>
<div :style="[baseStyles, overridingStyles]"></div>
<div :style="styleObject"></div>
</template>
```
::
Refer to the [Vue docs](https://vuejs.org/guide/essentials/class-and-style.html) for more information.
### Dynamic Styles With `v-bind`
You can reference JavaScript variable and expression within your style blocks with the v-bind function.
The binding will be dynamic, meaning that if the variable value changes, the style will be updated.
```vue
<script setup>
const color = ref("red")
</script>
<template>
<div class="text">hello</div>
</template>
<style>
.text {
color: v-bind(color);
}
</style>
```
### Scoped Styles
The scoped attribute allows you to style component in insolation. The styles declared with this attribute will only apply to this component.
```vue
<template>
<div class="example">hi</div>
</template>
<style scoped>
.example {
color: red;
}
</style>
```
### CSS Modules
You can use [CSS Modules](https://github.com/css-modules/css-modules) with the module attribute. Access it with the injected `$style` variable.
```vue
<template>
<p :class="$style.red">This should be red</p>
</template>
<style module>
.red {
color: red;
}
</style>
```
### Preprocessors Support
SFC style blocks support preprocessors syntax. Vite come with built-in support for .scss, .sass, .less, .styl and .stylus files without configuration. You just need to install them first, and they will be available directly in SFC with the lang attribute.
::code-group
```vue [SCSS]
<style lang="scss">
/* Write scss here */
</style>
```
```vue [Sass]
<style lang="sass">
/* Write sass here */
</style>
```
```vue [LESS]
<style lang="less">
/* Write less here */
</style>
```
```vue [Stylus]
<style lang="stylus">
/* Write stylus here */
</style>
```
::
You can refer to the [Vite CSS docs](https://vitejs.dev/guide/features.html#css) and the [@vitejs/plugin-vue docs](https://github.com/vitejs/vite-plugin-vue/tree/main/packages/plugin-vue).
For webpack users, refer to the [vue loader docs](https://vue-loader.vuejs.org/).
## Using PostCSS
Nuxt comes with postcss built-in. You can configure it in your `nuxt.config` file.
```ts [nuxt.config.ts]
export default defineNuxtConfig({
postcss: {
plugins: {
'postcss-nested': {}
"postcss-custom-media": {}
}
}
})
```
For proper syntax highlighting in SFC, you can use the postcss lang attribute.
```vue
<style lang="postcss">
/* Write stylus here */
</style>
```
By default, Nuxt comes with the following plugins already pre-configured:
- [postcss-import](https://github.com/postcss/postcss-import): Improves the `@import` rule
- [postcss-url](https://github.com/postcss/postcss-url): Transforms `url()` statements
- [autoprefixer](https://github.com/postcss/autoprefixer): Automatically adds vendor prefixes
- [cssnano](https://cssnano.co/): Minification and purge
##  Leveraging Layouts For Multiple Styles
If you need to style different parts of your application completely differently, you can use layouts.
Use different styles for different layouts.
```vue
<template>
<div class="default-layout">
<h1>Default Layout</h1>
<slot />
</div>
</template>
<style>
.default-layout {
color: red;
}
</style>
```
::ReadMore{link="docs/guide/directory-structure/layouts"}
::
## Third Party Libraries And Modules
Nuxt isn't opinionated when it comes to styling and provides you with a wide variety of options. You can use any styling tool that you want, such as popular libraries like [UnoCSS](https://unocss.dev/) or [Tailwind CSS](https://tailwindcss.com/).
The community and the Nuxt team have developed plenty of Nuxt modules to makes the integration easier.
You can discover them on the [modules section](https://nuxt.com/modules) of the website.
Here are a few modules to help you get started:
- [UnoCSS](https://nuxt.com/modules/unocss): Instant on-demand atomic CSS engine
- [Tailwind CSS](https://nuxt.com/modules/tailwindcss): Utility-first CSS framework
- [Fontaine](https://github.com/nuxt-modules/fontaine): Font metric fallback
- [Pinceau](https://pinceau.dev/): Adaptable styling framework
- [NuxtLabs UI](https://nuxt.com/modules/nuxtlabs-ui)
Nuxt modules provide you with a good developer experience out of the box, but remember that if your favorite tool doesn't have a module, it doesn't mean that you can't use it with Nuxt! You can configure it yourself for your own project. Depending on the tool, you might need to use a [Nuxt plugin](docs/guide/directory-structure/plugins) and/or [make your own module](/docs/guide/going-further/modules). Share them with the [community](https://nuxt.com/modules) if you do!
### Easily Load Webfonts
You can use [the Nuxt Google Fonts module](https://github.com/nuxt-modules/google-fonts) to load Google Fonts.
If you are using [UnoCSS](https://unocss.dev/integrations/nuxt), note that it comes with a [web fonts presets](https://unocss.dev/presets/web-fonts) to conveniently load fonts from common providers, including Google Fonts and more.
## Advanced
### Transitions
Nuxt comes with the same `<Transition>` element that Vue has, and also has support for the experimental [View Transitions API](/docs/getting-started/transitions#view-transitions-api-experimental).
::ReadMore{link="docs/features/transitions"}
::
### Font Advanced Optimization
We would recommend using [Fontaine](https://github.com/nuxt-modules/fontaine) to reduce your [CLS](https://web.dev/cls/). If you need something more advanced, consider creating a Nuxt module to extend the build process or the Nuxt runtime.
::alert{type="info"}
Always remember to take advantage of the various tools and techniques available in the Web ecosystem at large to make styling your application easier and more efficient. Whether you're using native CSS, a preprocessor, postcss, a UI library or a module, Nuxt has got you covered. Happy styling!
::
### LCP Avanced optimizations
You can do the following to speed-up the download of your global CSS files:
- Use a CDN so the files are physically closer to your users
- Compress your assets, ideally using Brotli
- Use HTTP2/HTTP3 for delivery
- Host your assets on the same domain (do not use a different subdomain)
Most of these things should be done for you automatically if you're using modern platforms like Cloudflare, Netlify or Vercel.
You can find an LCP optimization guide on [web.dev](https://web.dev/optimize-lcp/).
If all of your CSS is inlined by Nuxt, you can (experimentally) completely stop external CSS files from being referenced in your rendered HTML.
You can achieve that with a hook, that you can place in a module, or in your Nuxt configuration file.
```ts [nuxt.config.ts]
export default defineNuxtConfig({
hooks: {
'build:manifest': (manifest) => {
// find the app entry, css list
const css = manifest['node_modules/nuxt/dist/app/entry.js']?.css
if (css) {
// start from the end of the array and go to the beginning
for (let i = css.length - 1; i >= 0; i--) {
// if it starts with 'entry', remove it from the list
if (css[i].startsWith('entry')) css.splice(i, 1)
}
}
},
},
})
```