ant-design/docs/react/compatible-style.en-US.md

group	order	title
title Advanced	1	CSS Compatible

Default Style Compatibility

Ant Design supports the last 2 versions of modern browsers. If you need to be compatible with legacy browsers, please perform downgrade processing according to actual needs:

Feature	antd version	Compatibility	Minimum Chrome Version	Compatibility workaround
:where Selector	>=5.0.0	caniuse	Chrome 88	<StyleProvider hashPriority="high">
CSS Logical Properties	>=5.0.0	caniuse	Chrome 89	<StyleProvider transformers={[legacyLogicalPropertiesTransformer]}>

If you need to support older browsers, please use StyleProvider for degradation handling according to your actual requirements.

:where in selector

• antd version: >=5.0.0
• MDN: :where
• Browser Compatibility: caniuse
• Minimum Chrome Version Supported: 88
• Default Enabled: Yes

The CSS-in-JS feature of Ant Design uses the ":where" selector by default to lower the CSS selector specificity, reducing the additional cost of adjusting custom styles when upgrading for users. However, the compatibility of the ":where" syntax is relatively poor in older browsers (compatibility). In certain scenarios, if you need to support older browsers, you can use @ant-design/cssinjs to disable the default lowering of specificity (please ensure version consistency with antd).

import { StyleProvider } from '@ant-design/cssinjs';

// Config `hashPriority` to `high` instead of default `low`
// Which will remove `:where` wrapper
export default () => (
  <StyleProvider hashPriority="high">
    <MyApp />
  </StyleProvider>
);

It will turn :where to class selector:

--  :where(.css-bAMboO).ant-btn {
++  .css-bAMboO.ant-btn {
      color: #fff;
    }

Note: After turning off the :where downgrade, you may need to manually adjust the priority of some styles. Or you can use PostCSS plugin to raise application css selector priority. PostCSS provides many plugins can help on this. e.g:

• postcss-scopify
• postcss-increase-specificity
• postcss-add-root-selector

Raise priority through plugin:

--  .my-btn {
++  #root .my-btn {
      background: red;
    }

CSS Logical Properties

• antd version: >=5.0.0
• MDN：CSS Logical Properties
• Browser Compatibility: caniuse
• Minimum Chrome Version Supported: 89
• Default Enabled: Yes

To unify LTR and RTL styles, Ant Design uses CSS logical properties. For example, the original margin-left is replaced by margin-inline-start, so that it is the starting position spacing under both LTR and RTL. If you need to be compatible with older browsers, you can configure transformers through the StyleProvider of @ant-design/cssinjs:

import { legacyLogicalPropertiesTransformer, StyleProvider } from '@ant-design/cssinjs';

// `transformers` provides a way to transform CSS properties
export default () => (
  <StyleProvider transformers={[legacyLogicalPropertiesTransformer]}>
    <MyApp />
  </StyleProvider>
);

When toggled, styles will downgrade CSS logical properties:

.ant-modal-root {
-- inset: 0;
++ top: 0;
++ right: 0;
++ bottom: 0;
++ left: 0;
}

@layer

• antd version: >=5.17.0
• MDN：CSS @layer
• Browser Compatibility: caniuse
• Minimum Chrome Version Supported: 99
• Default Enabled: No

Ant Design supports configuring @layer for unified css priority downgrade since 5.17.0. After the downgrade, the style of antd will always be lower than the default CSS selector priority, so that users can override the style (please be sure to check the browser compatibility of @layer):

import { StyleProvider } from '@ant-design/cssinjs';

export default () => (
  <StyleProvider layer>
    <MyApp />
  </StyleProvider>
);

antd styles will be encapsulated in @layer to lower the priority:

++  @layer antd {
      :where(.css-bAMboO).ant-btn {
        color: #fff;
      }
++  }

Rem Adaptation

In responsive web development, there is a need for a convenient and flexible way to achieve page adaptation and responsive design. The px2remTransformer transformer can quickly and accurately convert pixel units in style sheets to rem units relative to the root element (HTML tag), enabling the implementation of adaptive and responsive layouts.

import { px2remTransformer, StyleProvider } from '@ant-design/cssinjs';

const px2rem = px2remTransformer({
  rootValue: 32, // 32px = 1rem; @default 16
});

export default () => (
  <StyleProvider transformers={[px2rem]}>
    <MyApp />
  </StyleProvider>
);

The resulting transformed styles:

 .px2rem-box {
-  width: 400px;
+  width: 12.5rem;
   background-color: green;
-  font-size: 32px;
+  font-size: 1rem;
   border: 10PX solid #f0f;
 }

 @media only screen and (max-width: 600px) {
   .px2rem-box {
     background-color: red;
-    margin: 10px;
+    margin: 0.3125rem;
   }
 }

Options

Parameter	Description	Type	Default
rootValue	Font size of the root element	number	16
precision	Decimal places for the converted value	number	5
mediaQuery	Whether to convert px in media queries	boolean	false

For more details, please refer to: px2rem.ts#Options

Shadow DOM Usage

Since <style /> tag insertion is different from normal DOM in Shadow DOM scenario, you need to use StyleProvider of @ant-design/cssinjs to configure the container property to set the insertion position:

import { StyleProvider } from '@ant-design/cssinjs';
import { createRoot } from 'react-dom/client';

const shadowRoot = someEle.attachShadow({ mode: 'open' });
const container = document.createElement('div');
shadowRoot.appendChild(container);
const root = createRoot(container);

root.render(
  <StyleProvider container={shadowRoot}>
    <MyApp />
  </StyleProvider>,
);

Compatible with Third-party Style Libraries

In some cases, you may need antd to coexist with other style libraries, such as Tailwind CSS, Emotion, styled-components, etc. Unlike traditional CSS solutions, these third-party libraries are often not easy to override antd styles by increasing CSS selector priority. You can configure @layer for antd to lower its CSS selector weight, and arrange @layer order to solve style override problems:

antd config @layer

import { StyleProvider } from '@ant-design/cssinjs';

export default () => (
  <StyleProvider layer>
    <MyApp />
  </StyleProvider>
);

TailwindCSS Arrange @layer

In global.css, adjust @layer to control the order of style override. Place tailwind-base before antd:

@layer tailwind-base, antd;

@layer tailwind-base {
  @tailwind base;
}
@tailwind components;
@tailwind utilities;

reset.css

If you use antd's reset.css style, you need to specify @layer for it to prevent the style from overriding antd:

@layer reset, antd;

@import url(reset.css) layer(reset);

With other CSS-in-JS libraries

After configuring @layer for antd, you don't need to do any additional configuration for other CSS-in-JS libraries. Your CSS-in-JS can completely override antd styles.

SSR Scene

When using SSR, styles are often rendered inline in HTML through <style />. At this time, please make sure that the styles with the specified @layer priority order are loaded before @layer is used.

❌ Wrong

<head>
  <!-- SSR Injection style -->
  <style>
    @layer antd {
      /** ... */
    }
  </style>

  <!-- css file contains @layer xxx, antd; -->
  <link rel="stylesheet" href="/b9a0m0b9o0o3.css" />
  <!-- or write @layer xxx, antd; in html directly -->
  <style>
    @layer xxx, antd;
  </style>
</head>

✅ Correct

<head>
  <!-- css file contains @layer xxx, antd; -->
  <link rel="stylesheet" href="/b9a0m0b9o0o3.css" />
  <!-- or write @layer xxx, antd; in html directly -->
  <style>
    @layer xxx, antd;
  </style>

  <!-- SSR Injection style -->
  <style>
    @layer antd {
      /** ... */
    }
  </style>
</head>