---
productId: material-ui
components: CssBaseline, ScopedCssBaseline
githubLabel: 'component: CssBaseline'
githubSource: packages/mui-material/src/CssBaseline
---
# CSS Baseline
The CssBaseline component helps to kickstart an elegant, consistent, and simple baseline to build upon.
{{"component": "@mui/docs/ComponentLinkHeader", "design": false}}
## Global reset
You might be familiar with [normalize.css](https://github.com/necolas/normalize.css), a collection of HTML element and attribute style-normalizations.
```jsx
import * as React from 'react';
import CssBaseline from '@mui/material/CssBaseline';
export default function MyApp() {
return (
{/* The rest of your application */}
);
}
```
## Scoping on children
However, you might be progressively migrating a website to Material UI, using a global reset might not be an option.
It's possible to apply the baseline only to the children by using the `ScopedCssBaseline` component.
```jsx
import * as React from 'react';
import ScopedCssBaseline from '@mui/material/ScopedCssBaseline';
import MyApp from './MyApp';
export default function MyApp() {
return (
{/* The rest of your application */}
);
}
```
⚠️ Make sure you import `ScopedCssBaseline` first to avoid box-sizing conflicts as in the above example.
## Approach
### Page
The `` and `` elements are updated to provide better page-wide defaults. More specifically:
- The margin in all browsers is removed.
- The default Material Design background color is applied.
It's using [`theme.palette.background.default`](/material-ui/customization/default-theme/?expand-path=$.palette.background) for standard devices and a white background for print devices.
- If `enableColorScheme` is provided to `CssBaseline`, native components color will be set by applying [`color-scheme`](https://web.dev/articles/color-scheme) on ``.
The value used is provided by the theme property `theme.palette.mode`.
### Layout
- `box-sizing` is set globally on the `` element to `border-box`.
Every element—including `*::before` and `*::after` are declared to inherit this property,
which ensures that the declared width of the element is never exceeded due to padding or border.
### Scrollbars
:::error
This API is deprecated.
Consider using [color-scheme](#color-scheme) instead.
:::
The colors of the scrollbars can be customized to improve the contrast (especially on Windows). Add this code to your theme (for dark mode).
```jsx
import darkScrollbar from '@mui/material/darkScrollbar';
const theme = createTheme({
components: {
MuiCssBaseline: {
styleOverrides: (themeParam) => ({
body: themeParam.palette.mode === 'dark' ? darkScrollbar() : null,
}),
},
},
});
```
Be aware, however, that using this utility (and customizing `-webkit-scrollbar`) forces macOS to always show the scrollbar.
### Color scheme
This API is introduced in @mui/material (v5.1.0) for switching between `"light"` and `"dark"` modes of native components such as scrollbar, using the `color-scheme` CSS property.
To enable it, you can set `enableColorScheme=true` as follows:
```jsx
// or
{/* The rest of your application using color-scheme*/}
```
### Typography
- No base font-size is declared on the ``, but 16px is assumed (the browser default).
You can learn more about the implications of changing the `` default font size in [the theme documentation](/material-ui/customization/typography/#html-font-size) page.
- Set the `theme.typography.body1` style on the `` element.
- Set the font-weight to `theme.typography.fontWeightBold` for the `` and `` elements.
- Custom font-smoothing is enabled for better display of the Roboto font.
## Customization
Head to the [global customization](/material-ui/customization/how-to-customize/#4-global-css-override) section of the documentation to change the output of these components.