This PR is a follow up of #18815 and #18816, but this time let's migrate
the `supports` theme keys.
Let's imagine you have the following Tailwind CSS v3 configuration:
```ts
export default {
content: ['./src/**/*.html'],
theme: {
extend: {
supports: {
// Automatically handled by bare values (using CSS variable as the value)
foo: 'foo: var(--foo)', // parentheses are optional
bar: '(bar: var(--bar))',
// Not automatically handled because names differ
baz: 'qux: var(--foo)',
// ^^^ ^^^ ← different names
// Custom
grid: 'display: grid',
},
},
},
}
```
Then we would generate the following Tailwind CSS v4 CSS:
```css
@custom-variant supports-baz {
@supports (qux: var(--foo)) {
@slot;
}
}
@custom-variant supports-grid {
@supports (display: grid) {
@slot;
}
}
```
Notice how we didn't generate a custom variant for `data-foo` or
`data-bar` because those are automatically handled by bare values.
I also went with the longer form of `@custom-variant`, we could use the
single selector approach, but that felt less clear to me.
```css
@custom-variant supports-baz (@supports (qux: var(--foo)));
@custom-variant supports-grid (@supports (display: grid));
```
---------
Co-authored-by: Jordan Pittman <thecrypticace@gmail.com>
This PR is similar to and a follow up of #18815, but this time to
migrate the `data` theme keys.
Let's imagine you have the following Tailwind CSS v3 configuration:
```ts
export default {
content: ['./src/**/*.html'],
theme: {
extend: {
data: {
// Automatically handled by bare values
foo: 'foo',
// ^^^ ^^^ ← same names
// Not automatically handled by bare values
bar: 'baz',
// ^^^ ^^^ ← different names
// Completely custom
checked: 'ui~="checked"',
},
},
},
}
```
Then we would generate the following Tailwind CSS v4 CSS:
```css
@custom-variant data-bar (&[data-baz]);
@custom-variant data-checked (&[data-ui~="checked"]);
```
Notice how we didn't generate a custom variant for `data-foo` because
those are automatically handled by bare values.
This PR migrates `aria` theme keys when migrating from Tailwind CSS v3
to v4.
While working on improving some of the error messages to get more
insights into why migrating the JS file changed
(https://github.com/tailwindlabs/tailwindcss/pull/18808), I ran into an
issue where I couldn't think of a good comment to why `aria` theme keys
were not being migrated. (Internally we have `aria` "blocked").
So instead of figuring out a good error message..., I just went ahead
and added the migration for `aria` theme keys.
Let's imagine you have the following Tailwind CSS v3 configuration:
```ts
export default {
content: ['./src/**/*.html'],
theme: {
extend: {
aria: {
// Built-in (not really, but visible because of intellisense)
busy: 'busy="true"',
// Automatically handled by bare values
foo: 'foo="true"',
// ^^^ ^^^ ← same names
// Not automatically handled by bare values because names differ
bar: 'baz="true"',
// ^^^ ^^^ ← different names
// Completely custom
asc: 'sort="ascending"',
desc: 'sort="descending"',
},
},
},
}
```
Then we would generate the following Tailwind CSS v4 CSS:
```css
@custom-variant aria-bar (&[aria-baz="true"]);
@custom-variant aria-asc (&[aria-sort="ascending"]);
@custom-variant aria-desc (&[aria-sort="descending"]);
```
Notice how we didn't generate a custom variant for `aria-busy` or
`aria-foo` because those are automatically handled by bare values.
We could also emit a comment near the CSS to warn about the fact that
`@custom-variant` will always be sorted _after_ any other built-in
variants.
This could result in slightly different behavior, or different order of
classes when using `prettier-plugin-tailwindcss`.
I don't know how important this is, because before this PR we would just
use `@config './tailwind.config.js';`.
Edit: when using the `@config` we override `aria` and extend it, which
means that it would be in the expected order 🤔
---------
Co-authored-by: Jordan Pittman <thecrypticace@gmail.com>
Since we (optionally) support source maps now it's possible that a later
PostCSS plugin that *still* does url rewriting might fail to do so
correctly because nodes will have preserved source locations in dev
builds where before we "pretended" that everything came from the
original file.
But, because we can't know if such a plugin is present, disabling this
behavior when source maps are enabled could cause issues *and* would be
a breaking change.
I wish everything *could just work* here but realistically we can't know
what plugins have run before our PostCSS plugin or what plugins will run
after so the best option (I think) we can offer here is to allow users
to disable url rewriting at the plugin level.
Fixes#16700
This PR tweaks the dropdown arrow added to an input by Chrome when it
has a `list` attribute pointing to a `<datalist>`.
Right now the arrow isn't centered vertically:
<img width="227" height="58" alt="Screenshot 2025-07-14 at 15 41 50"
src="https://github.com/user-attachments/assets/b354a5e8-432d-432d-bfe4-f7b6f6683548"
/>
The cause of this is the line height being inherited into the pseudo
element which controls how the marker is positioned. I *think* this is
because it's being drawn with unicode symbols but I'm not sure. It could
just be from the `list-item` display.
After this PR changes the line height its centered again:
<img width="227" height="58" alt="Screenshot 2025-07-14 at 15 42 05"
src="https://github.com/user-attachments/assets/1afa1f33-cc28-4b1f-9e04-e546f6848f57"
/>
Some notes:
This only affects Chrome and also does not appear to cause issues for
date/time inputs. While weird that this pseudo is the one used for a
`<datalist>` marker it is indeed correct.
Fixes#18499
Can use this Play to test the change:
https://play.tailwindcss.com/jzT35CRpr0
---------
Co-authored-by: Jonathan Reinink <jonathan@reinink.ca>
Closes#18381
* [Changelog for Vite 7.0.0
(2025-06-24)](https://github.com/vitejs/vite/blob/main/packages/vite/CHANGELOG.md#700-2025-06-24)
Starting from Vite 7, Node 18 support will be dropped, which doesn't
really affect Tailwind. It might be worth mentioning in the
documentation that the recommended minimum Node versions are 20.19 and
22.12.
Vite 7 is only available in ESM format, which is also not an issue.
Vite's browser support aligns with the v4 guidelines:
```
Chrome 87 → 107 (tw: 111)
Edge 88 → 107 (tw: 111)
Firefox 78 → 104 (tw: 128)
Safari 14.0 → 16.0 (tw: 16.4)
```
* [Vite 7 - Browser
Support](https://vite.dev/guide/migration.html#default-browser-target-change)
* [Tailwind CSS v4 - Browser
Support](https://tailwindcss.com/docs/compatibility#browser-support)
So, at first glance, there's nothing more to do except enabling support
for these versions.
---------
Co-authored-by: Jordan Pittman <jordan@cryptica.me>
Description:
This pull request corrects minor typos in comments and improves clarity
in two files:
- Fixes a typo in a comment within migrate-js-config.ts ("migrateable" →
"migratable").
- Refines a comment in wasm.test.ts for better readability.
No functional code changes are included.
This PR improves error messages when `@apply` fails. Right now it gives
you a generic error message that you cannot apply a certain utility.
```css
.foo {
@apply bg-red-500;
}
```
Would result in:
```
Cannot apply unknown utility class: bg-red-500
```
However, there are some situations where we can give you more context
about what's happening.
### Missing `@import "tailwindcss"` or `@reference`
If you are in a Vue file for example, and you have the following code:
```vue
<template>
<div class="foo"></div>
</template>
<style>
.foo {
@apply bg-red-500;
}
</style>
```
Then this will now result in:
```
Cannot apply unknown utility class `bg-white`. Are you using CSS modules or similar and missing `@reference`? https://tailwindcss.com/docs/functions-and-directives#reference-directive
```
We do this by checking if we found a `@tailwind utilities` or
`@reference`. If not, we throw this more specific error.
### Explicitly excluded classes via `@source not inline('…')`
Or via the legacy `blocklist` from a JS config.
If you then have the following file:
```css
@import "tailwindcss";
@source not inline('bg-white');
.foo {
@apply bg-white;
}
```
Then this will now result in:
```
Cannot apply utility class `bg-white` because it has been explicitly disabled: https://tailwindcss.com/docs/detecting-classes-in-source-files#explicitly-excluding-classes
```
We do this by checking if the class was marked as invalid.
### Applying unprefixed class in prefix mode
If you have the prefix option configured, but you are applying a
non-prefixed class, then we will show the following error:
Given this input:
```css
@import "tailwindcss" prefix(tw);
.foo {
@apply underline;
}
```
The following error is thrown:
```
Cannot apply unprefixed utility class `underline`. Did you mean `tw:underline`?
```
### Applying known utilities with unknown variants
If you have unknown variants, then we will list them as well if the base
utility does compile correctly.
Given this input:
```css
@import "tailwindcss";
.foo {
@apply hocus:hover:pocus:bg-red-500;
}
```
The following error is thrown:
```
Cannot apply utility class `hocus:hover:pocus:bg-red-500` because the `hocus` and `pocus` variants do not exist.
```
## Test plan
1. Everything behaves the same, but the error messages give more
details.
2. Updated tests with new error messages
3. Added new unit tests to verify the various scenarios
4. Added a Vue specific integration test with a `<style>…</style>` block
using `@apply`
[ci-all] There are some newlines here and there, let's verify that they
work identically on all platforms.
---------
Co-authored-by: Jonathan Reinink <jonathan@reinink.ca>
This PR fixes an issue where an error such as:
<img width="1702" alt="image"
src="https://github.com/user-attachments/assets/4e6f75c7-3182-4497-939e-96cff08c55ae"
/>
Will be thrown during the upgrade process. This can happen when you are
using `pnpm` and your CSS file includes a `@import "tailwindcss";`. In
this scenario, `tailwindcss` will be loaded from a shared `.pnpm` folder
outside of the current working directory.
In this case, we are also not interested in migrating _that_ file, but
we also don't want the upgrade process to just crash.
I didn't see an option to ignore errors like this, so wrapped it in a
try/catch instead.
It also fixes another issue where if you are using a pnpm workspace and
run the upgrade tool from the root, then it throws you an error that you
cannot add dependencies to the workspace root unless `-w` or
`--workspace-root` flags are passed.
For this, we disable the check entirely using the
`--ignore-workspace-root-check` flag. If we always used the
`--workspace-root` flag, then the dependencies would always be added to
the root, regardless of where you are running the script from which is
not what we want.
## Test plan
Before:
<img width="1816" alt="image"
src="https://github.com/user-attachments/assets/78246876-3eb6-4539-a557-d3d366f1b3a3"
/>
After:
<img width="1816" alt="image"
src="https://github.com/user-attachments/assets/a65e4421-d7c5-4d83-b35d-934708543e25"
/>
Before:
<img width="1816" alt="image"
src="https://github.com/user-attachments/assets/53772661-2c4a-4212-84d9-a556a0ad320f"
/>
After:
<img width="1816" alt="image"
src="https://github.com/user-attachments/assets/5bfaf20e-34b8-44fd-9b59-e72d36738879"
/>
This PR improves the upgrade tool by making sure that we don't migrate
CSS declarations in `<style>…</style>` blocks.
We do this by making sure that:
1. We detect a declaration, the current heuristic is that the candidate
is:
- Preceded by whitespace
- Followed by a colon and whitespace
```html
<style>
.foo {
flex-shrink: 0;
^ ^^
}
</style>
```
2. We are in a `<style>…</style>` block
```html
<style>
^^^^^^
.foo {
flex-shrink: 0;
}
</style>
^^^^^^^^
```
The reason we have these 2 checks is because just relying on the first
heuristic alone, also means that we will not be migrating keys in JS
objects, because they typically follow the same structure:
```js
let classes = {
flex: 0,
^ ^^
}
```
Another important thing to note is that we can't just ignore anything in
between `<style>…</style>` blocks, because you could still be using
`@apply` that we _do_ want to migrate.
Last but not least, the first heuristics is not perfect either. If you
are writing minified CSS then this will likely fail if there is no
whitespace around the candidate.
But my current assumption is that nobody should be writing minified CSS,
and minified CSS will very likely be generated and gitignored. In either
situation, replacements in minified CSS will not be any worse than it is
today.
I'm open to suggestions for better heuristics.
## Test plan
1. Added an integration test that verifies that we do migrate `@apply`
and don't migrate the `flex-shrink: 0;` declaration.
Fixes: #17975
This PR makes the migrations for templates much faster. To make this
work, I also had to move things around a bit (so you might want to check
this PR commit by commit). I also solved an issue by restructuring the
code.
### Performance
For starters, we barely applied any caching when migrating candidates
from α to β. The problem with this is that in big projects the same
candidates will appear _everywhere_, so caching is going to be useful
here.
One of the reasons why we didn't do any caching is that some migrations
were checking if a migration is actually safe to do. To do this, we were
checking the `location` (the location of the candidate in the template).
Since this location is unique for each template, caching was not
possible.
So the first order of business was to hoist the `isSafeMigration` check
up as the very first thing we do in the migration.
If we do this first, then the only remaining code relies on the
`DesignSystem`, `UserConfig` and `rawCandidate`.
In a project, the `DesignSystem` and `UserConfig` will be the same
during the migration, only the `rawCandidate` will be different which
means that we can move all this logic in a good old `DefaultMap` and
cache the heck out of it.
Running the numbers on our Tailwind Plus repo, this results in:
```
Total seen candidates: 2 211 844
Total migrated candidates: 7 775
Cache hits: 1 575 700
```
That's a lot of work we _don't_ have to do. Looking at the timings, the
template migration step goes from ~45s to ~10s because of this.
Another big benefit of this is that this makes migrations _actually_
safe. Before we were checking if a migration was safe to do in specific
migrations. But other migrations were still printing the candidate which
could still result in an unsafe migration.
For example when migrating the `blur` and the `shadow` classes, the
`isSafeMigration` was used. But if the input was `!flex` then the safety
check wasn't even checked in this specific migration.
### Safe migrations
Also made some changes to the `isSafeMigration` logic itself. We used to
start by checking the location, but thinking about the problem again,
the actual big problem we were running into is classes that are short
like `blur`, and `shadow` because they could be used in other contexts
than a Tailwind CSS class.
Inverting this logic means that more specific Tailwind CSS classes will
very likely _not_ cause any issues at all.
For example:
- If you have variants: `hover:focus:flex`
- If you have arbitrary properties: `[color:red]`
- If you have arbitrary values: `bg-[red]`
- If you have a modifier: `bg-red-500/50`
- If you have a `-` in the name: `bg-red-500`
Even better if we can't parse a candidate at all, we can skip the
migrations all together.
This brings us to the issue in #17974, one of the issues was already
solved by just hoisting the `isSafeMigration`. But to make the issue was
completely solved I also made sure that in Vue attributes like
`:active="…"` are also considered unsafe (note: `:class` is allowed).
Last but not least, in case of the `!duration` that got replaced with
`duration!` was solved by verifying that the candidate actually produces
valid CSS. We can compute the signature for this class.
The reason this wasn't thrown away earlier is because we can correctly
parse `duration` but `duration` on its own doesn't exist,
`duration-<number>` does exist as a functional utility which is why it
parsed in the first place.
Fixes: #17974
## Test plan
1. Ran the tool on our Tailwind UI Templates repo to compare the new
output with the "old" behavior and there were no differences in output.
2. Ran the tool on our Tailwind Plus repo, and the template migration
step went from ~45s to ~10s.
3. Added additional tests to verify the issues in #17974 are fixed.
[ci-all] let's run this on all CI platforms...
Fixes#16156
## Summary
This PR adds a new 3 -> 4 template migration that changes the casing of
in both utility values and modifier values from camelCase to kebab-case
to match the updated CSS variable names.
## Test plan
- Added integration test, see the diff in the PR.
Here is everything you need to know about this upgrade. Please take a
good look at what changed and the test results before merging this pull
request.
### What changed?
#### ✳️ dedent (1.5.3 → 1.6.0) · [Repo](https://github.com/dmnd/dedent)
· [Changelog](https://github.com/dmnd/dedent/blob/main/CHANGELOG.md)
<details>
<summary>Release Notes</summary>
<h4><a
href="https://github.com/dmnd/dedent/releases/tag/v1.6.0">1.6.0</a></h4>
<blockquote><h2 dir="auto">What's Changed</h2>
<ul dir="auto">
<li>feat: add <code class="notranslate">trimWhitespace</code> option by
<a href="https://bounce.depfu.com/github.com/43081j">@43081j</a> in <a
href="https://bounce.depfu.com/github.com/dmnd/dedent/pull/97">#97</a>
</li>
</ul>
<h2 dir="auto">New Contributors</h2>
<ul dir="auto">
<li>
<a href="https://bounce.depfu.com/github.com/43081j">@43081j</a> made
their first contribution in <a
href="https://bounce.depfu.com/github.com/dmnd/dedent/pull/97">#97</a>
</li>
</ul>
<p dir="auto"><strong>Full Changelog</strong>: <a
href="https://bounce.depfu.com/github.com/dmnd/dedent/compare/v1.5.3...v1.6.0"><tt>v1.5.3...v1.6.0</tt></a></p></blockquote>
<p><em>Does any of this look wrong? <a
href="https://depfu.com/packages/npm/dedent/feedback">Please let us
know.</a></em></p>
</details>
<details>
<summary>Commits</summary>
<p><a
href="90644fe0be...ab2ce25762">See
the full diff on Github</a>. The new version differs by 2 commits:</p>
<ul>
<li><a
href="ab2ce25762"><code>1.6.0
(#98)</code></a></li>
<li><a
href="86902f7c97"><code>feat:
add `trimWhitespace` option (#97)</code></a></li>
</ul>
</details>
---
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Closes#15806
This PR adds a new `postinstall` script to `@tailwindcss/oxide` that
will attempt to download the platform-specific optional dependency to
avoid issues when the package manager does not do that automatically
(see #15806). The implementation for this is fairly simple: The npm
package is downloaded from the official npm servers and extracted into
the `node_modules` directory of the `@tailwidncss/oxide` installation.
## Test plan
Since we still lack a solid repro of #15806, the way I tested this
change was to manually remove all automatically-installed optional
dependencies and then running the postinstall script manually. The
script then downloads the right version package which makes the import
to `@tailwidncss/oxide` work. An appropriate integration test was added
too.
I furthermore also validated that:
- This works across CI platforms [ci-all]
- The postinstall script bails out when running `pnpm install` in the
dev setup. This is necessary since doing the initial install won't have
any binary dependencies yet so it would download invalid versions from
npm (as the version numbers locally refer to the last released version).
We can safely bail out here though since this was never an issue with
local development.
- The postinstall script does not do anything when the
`@tailwindcss/oxide` library is added _unless_ the issue is detected.
[ci-all]
---------
Co-authored-by: Robin Malfait <malfait.robin@gmail.com>
Closes#13694Closes#13591
# Source Maps Support for Tailwind CSS
This PR adds support for source maps to Tailwind CSS v4 allowing us to
track where styles come from whether that be user CSS, imported
stylesheets, or generated utilities. This will improve debuggability in
browser dev tools and gives us a good foundation for producing better
error messages. I'll go over the details on how end users can enable
source maps, any limitations in our implementation, changes to the
internal `compile(…)` API, and some details and reasoning around the
implementation we chose.
## Usage
### CLI
Source maps can be enabled in the CLI by using the command line argument
`--map` which will generate an inline source map comment at the bottom
of your CSS. A separate file may be generated by passing a file name to
`--map`:
```bash
# Generates an inline source map
npx tailwindcss -i input.css -o output.css --map
# Generates a separate source map file
npx tailwindcss -i input.css -o output.css --map output.css.map
```
### PostCSS
Source maps are supported when using Tailwind as a PostCSS plugin *in
development mode only*. They may or may not be enabled by default
depending on your build tool. If they are not you may be able to
configure them within your PostCSS config:
```jsonc
// package.json
{
// …
"postcss": {
"map": { "inline": true },
"plugins": {
"@tailwindcss/postcss": {},
},
}
}
```
### Vite
Source maps are supported when using the Tailwind CSS Vite plugin in
*development mode only* by enabling the `css.devSourcemap` setting:
```js
import tailwindcss from "@tailwindcss/vite";
import { defineConfig } from "vite";
export default defineConfig({
plugins: [tailwindcss()],
css: {
devSourcemap: true,
},
})
```
Now when a CSS file is requested by the browser it'll have an inline
source map comment that the browser can use.
## Limitations
- Production build source maps are currently disabled due to a bug in
Lightning CSS. See
https://github.com/parcel-bundler/lightningcss/pull/971 for more
details.
- In Vite, minified CSS build source maps are not supported at all. See
https://github.com/vitejs/vite/issues/2830 for more details.
- In PostCSS, minified CSS source maps are not supported. This is due to
the complexity required around re-associating every AST node with a
location in the generated, optimized CSS. This complexity would also
have a non-trivial performance impact.
## Testing
Here's how to test the source map functionality in different
environments:
### Testing the CLI
1. Setup typical project that the CLI can use and with sources to scan.
```css
@import "tailwindcss";
@utilty my-custom-utility {
color: red;
}
/* to test `@apply` */
.card {
@apply bg-white text-center shadow-md;
}
```
2. Build with source maps:
```bash
bun /path/to/tailwindcss/packages/@tailwindcss-cli/src/index.ts --input input.css -o output.css --map
```
3. Open Chrome DevTools, inspect an element with utility classes, and
you should see rules pointing to `input.css` or
`node_modules/tailwindcss/index.css`
### Testing with Vite
Testing in Vite will require building and installing necessary files
under `dist/*.tgz`.
1. Create a Vite project and enable source maps in `vite.config.js`:
```js
import tailwindcss from "@tailwindcss/vite";
import { defineConfig } from "vite";
export default defineConfig({
plugins: [tailwindcss()],
css: {
// This line is required for them to work
devSourcemap: true,
},
})
```
2. Add a component that uses Tailwind classes and custom CSS:
```jsx
// ./src/app.jsx
export default function App() {
return (
<div className="bg-blue-500 my-custom-class">
Hello World
</div>
)
}
```
```css
/* ./src/styles.css */
@import "tailwindcss";
@utilty my-custom-utility {
color: red;
}
/* to test `@apply` */
.card {
@apply bg-white text-center shadow-md;
}
```
3. Run `npm run dev`, open DevTools, and inspect elements to verify
source mapping works for both utility classes and custom CSS.
### Testing with PostCSS CLI
1. Create a test file and update your PostCSS config:
```css
/* input.css */
@import "tailwindcss";
@layer components {
.card {
@apply p-6 rounded-lg shadow-lg;
}
}
```
```jsonc
// package.json
{
// …
"postcss": {
"map": {
"inline": true
},
"plugins": {
"/path/to/tailwindcss/packages/packages/@tailwindcss-postcss/src/index.ts": {}
}
}
}
```
2. Run PostCSS through Bun:
```bash
bunx --bun postcss ./src/index.css -o out.css
```
3. Inspect the output CSS - it should include an inline source map
comment at the bottom.
### Testing with PostCSS + Next.js
Testing in Next.js will require building and installing necessary files
under `dist/*.tgz`. However, I've not been able to get CSS source maps
to work in Next.js without this hack:
```js
const nextConfig: NextConfig = {
// next.js overwrites config.devtool so we prevent it from doing so
// please don't actually do this…
webpack: (config) =>
Object.defineProperty(config, "devtool", {
get: () => "inline-source-map",
set: () => {},
}),
};
```
This is definitely not supported and also doesn't work with turbopack.
This can be used to test them temporarily but I suspect that they just
don't work there.
### Manual source map analysis
You can analyze source maps using Evan Wallace's [Source Map
Visualization](https://evanw.github.io/source-map-visualization/) tool
which will help to verify the accuracy and quality of source maps. This
is what I used extensively while developing this implementation.
It'll help verify that custom, user CSS maps back to itself in the
input, that generated utilities all map back to `@tailwind utilities;`,
that source locations from imported files are also handled correctly,
etc… It also highlights the ranges of stuff so it's easy to see if there
are off-by-one errors.
It's easiest to use inline source maps with this tool because you can
take the CSS file and drop it on the page and it'll analyze it while
showing the file content.
If you're using Vite you'll want to access the CSS file with `?direct`
at the end so you don't get a JS module back.
## Implementation
The source map implementation follows the ECMA-426 specification and
includes several key components to aid in that goal:
### Source Location Tracking
Each emittable AST node in the compilation pipeline tracks two types of
source locations:
- `src`: Original source location - [source file, start offset, end
offset]
- `dst`: Generated source location - [output file, start offset, end
offset]
This dual tracking allows us to maintain mappings between the original
source and generated output for things like user CSS, generated
utilities, uses of `@apply`, and tracking theme variables.
It is important to note that source locations for nodes _never overlap_
within a file which helps simplify source map generation. As such each
type of node tracks a specific piece of itself rather than its entire
"block":
| Node | What a `SourceLocation` represents |
| ----------- |
---------------------------------------------------------------- |
| Style Rule | The selector |
| At Rule | Rule name and params, includes the `@` |
| Declaration | Property name and value, excludes the semicolon |
| Comment | The entire comment, includes the start `/*` and end `*/`
markers |
### Windows line endings when parsing CSS
Because our AST tracks nodes through offsets we must ensure that any
mutations to the file do *not* change the lenth of the string. We were
previously replacing `\r\n` with `\n` (see [filter code
points](https://drafts.csswg.org/css-syntax/#css-filter-code-points)
from the spec) — which changes the length of the string and all offsets
may end up incorrect. The CSS parser was updated to handle the CRLF
token directly by skipping over the `\r` and letting remaining code
handle `\n` as it did previously. Some additional tweaks were required
when "peeking" the input but those changes were fairly small.
### Tracking of imports
Source maps need paths to the actual imported stylesheets but the
resolve step for stylesheets happens inside the call to `loadStylesheet`
which make the file path unavailable to us. Because of this the
`loadStylesheet` API was augmented such that it has to return a `path`
property that we can then use to identify imported sources. I've also
made the same change to the `loadModule` API for consistency but nothing
currently uses this property.
The `path` property likely makes `base` redundant but elminating that
(if we even want to) is a future task.
### Optimizing the AST
Our optimization pass may intoduce some nodes, for example, fallbacks we
create for `@property`. These nodes are linked back to `@tailwind
utilities` as ultimately that is what is responsible for creating them.
### Line Offset Tables
A key component to our source map generation is the line offset table,
which was inspired by some ESBuild internals. It stores a sorted list of
offsets for the start of each line allowing us to translate offsets to
line/column `Position`s in `O(log N)` time and from `Position`s to
offsets in `O(1)` time. Creation of the table takes `O(N)` time.
This means that we can store code point offsets for source locations and
not have to worry about computing or tracking line/column numbers during
parsing and serialization. Only when a source map is generated do these
offsets need to be computed. This ensures the performance penalty when
not using source maps is minimal.
### Source Map Generation
The source map returned by `buildSourceMap()` is designed to follow the
[ECMA-426 spec](https://tc39.es/ecma426). Because that spec is not
completely finalized we consider the result of `buildSourceMap()` to be
internal API that may change as the spec chamges.
The produces source map is a "decoded" map such that all sources and
mappings are in an object graph. A library like `source-map-js` must be
used to convert this to an encoded source map of the right version where
mappings are encoded with base 64 VLQs.
Any specific integration (Vite, PostCSS, etc…) can then use
`toSourceMap()` from `@tailwindcss/node` to convert from the internal
source map to an spec-compliant encoded source map that can be
understood by other tools.
### Handling minification in Lightning
Since we use Lightning CSS for optimization, and it takes in an input
map, we generate an encoded source map that we then pass to lightning.
The output source map *from lighting itself* is then passed back in
during the second optimization pass. The final map is then passed from
lightning to the CLI (but not Vite or PostCSS — see the limitations
section for details).
In some cases we have to "fix up" the output CSS. When this happens we
use `magic-string` to do the replacement in a way that is trackable and
`@amppproject/remapping` to map that change back onto the original
source map. Once the need for these fix ups disappear these dependencies
can go away.
Notes:
- The accuracy of source maps run though lightning is reduced as it only
tracks on a per-rule level. This is sufficient enough for browser dev
tools so should be fine.
- Source maps during optimization do not function properly at this time
because of a bug in Lightning CSS regarding license comments. Once this
bug is fixed they will start working as expected.
### How source locations flow through the system
1. During initial CSS parsing, source locations are preserved.
2. During parsing these source locations are also mapped to the
destinations which supports an optimization for when no utilities are
generated.
3. Throughout the compilation process, transformations maintain source
location data
4. Generated utilities are explicitly pointed to `@tailwind utilities`
unless generated by `@apply`.
5. When optimization is enabled, source maps are remapped through
lightningcss
6. Final source maps are written in the requested format (inline or
separate file)
This PR introduces a vastly improved upgrade migrations system, to
migrate your codebase and modernize your utilities to make use of the
latest variants and utilities.
It all started when I saw this PR the other day:
https://github.com/tailwindlabs/tailwindcss/pull/17790
I was about to comment "Don't forget to add a migration". But I've been
thinking about a system where we can automate this process away. This PR
introduces this system.
This PR introduces upgrade migrations based on the internal Design
System, and it mainly updates arbitrary variants, arbitrary properties
and arbitrary values.
## The problem
Whenever we ship new utilities, or you make changes to your CSS file by
introducing new `@theme` values, or adding new `@utility` rules. It
could be that the rest of your codebase isn't aware of that, but you
could be using these values.
For example, it could be that you have a lot of arbitrary properties in
your codebase, they look something like this:
```html
<div class="[color-scheme:dark] [text-wrap:balance]"></div>
```
Whenever we introduce new features in Tailwind CSS, you probably don't
keep an eye on the release notes and update all of these arbitrary
properties to the newly introduced utilities.
But with this PR, we can run the upgrade tool:
```console
npx -y @tailwindcss/upgrade@latest
```
...and it will upgrade your project to use the new utilities:
```html
<div class="scheme-dark text-balance"></div>
```
It also works for arbitrary values, for example imagine you have classes
like this:
```html
<!-- Arbitrary property -->
<div class="[max-height:1lh]"></div>
<!-- Arbitrary value -->
<div class="max-h-[1lh]"></div>
```
Running the upgrade tool again:
```console
npx -y @tailwindcss/upgrade@latest
```
... gives you the following output:
```html
<!-- Arbitrary property -->
<div class="max-h-lh"></div>
<!-- Arbitrary value -->
<div class="max-h-lh"></div>
```
This is because of the original PR I mentioned, which introduced the
`max-h-lh` utilities.
A nice benefit is that this output only has 1 unique class instead of 2,
which also potentially reduces the size of your CSS file.
It could also be that you are using arbitrary values where you (or a
team member) didn't even know an alternative solution existed.
E.g.:
```html
<div class="w-[48rem]"></div>
```
After running the upgrade tool you will get this:
```html
<div class="w-3xl"></div>
```
We can go further though. Since the release of Tailwind CSS v4, we
introduced the concept of "bare values". Essentially allowing you to
type a number on utilities where it makes sense, and we produce a value
based on that number.
So an input like this:
```html
<div class="border-[123px]"></div>
```
Will be optimized to just:
```html
<div class="border-123"></div>
```
This can be very useful for complex utilities, for example, how many
times have you written something like this:
```html
<div class="grid-cols-[repeat(16,minmax(0,1fr))]"></div>
```
Because up until Tailwind CSS v4, we only generated 12 columns by
default. But since v4, we can generate any number of columns
automatically.
Running the migration tool will give you this:
```html
<div class="grid-cols-16"></div>
```
### User CSS
But, what if I told you that we can keep going...
In [Catalyst](https://tailwindcss.com/plus/ui-kit) we often use classes
that look like this for accessibility reasons:
```html
<div class="text-[CanvasText] bg-[Highlight]"></div>
```
What if you want to move the `CanvasText` and `Highlight` colors to your
CSS:
```css
@import "tailwincdss";
@theme {
--color-canvas: CanvasText;
--color-highlight: Highlight;
}
```
If you now run the upgrade tool again, this will be the result:
```html
<div class="text-canvas bg-highlight"></div>
```
We never shipped a `text-canvas` or `bg-highlight` utility, but the
upgrade tool uses your own CSS configuration to migrate your codebase.
This will keep your codebase clean, consistent and modern and you are in
control.
Let's look at one more example, what if you have this in a lot of
places:
```html
<div class="[scrollbar-gutter:stable]"></div>
```
And you don't want to wait for the Tailwind CSS team to ship a
`scrollbar-stable` (or similar) feature. You can add your own utility:
```css
@import "tailwincdss";
@utility scrollbar-stable {
scrollbar-gutter: stable;
}
```
```html
<div class="scrollbar-stable"></div>
```
## The solution — how it works
There are 2 big things happening here:
1. Instead of us (the Tailwind CSS team) hardcoding certain migrations,
we will make use of the internal `DesignSystem` which is the source of
truth for all this information. This is also what Tailwind CSS itself
uses to generate the CSS file.
The internal `DesignSystem` is essentially a list of all:
1. The internal utilities
2. The internal variants
3. The default theme we ship
4. The user CSS
1. With custom `@theme` values
2. With custom `@custom-variant` implementations
3. With custom `@utility` implementations
2. The upgrade tool now has a concept of `signatures`
The signatures part is the most interesting one, and it allows us to be
100% sure that we can migrate your codebase without breaking anything.
A signature is some unique identifier that represents a utility. But 2
utilities that do the exact same thing will have the same signature.
To make this work, we have to make sure that we normalize values. One
such value is the selector. I think a little visualization will help
here:
| UTILITY | GENERATED SIGNATURE |
| ---------------- | ----------------------- |
| `[display:flex]` | `.x { display: flex; }` |
| `flex` | `.x { display: flex; }` |
They have the exact same signature and therefore the upgrade tool can
safely migrate them to the same utility.
For this we will prefer the following order:
1. Static utilities — essentially no brackets. E.g.: `flex`,
`grid-cols-2`
2. Arbitrary values — e.g.: `max-h-[1lh]`, `border-[2px]`
3. Arbitrary properties — e.g.: `[color-scheme:dark]`, `[display:flex]`
We also have to canonicalize utilities to there minimal form.
Essentially making sure we increase the chance of finding a match.
```
[display:_flex_] → [display:flex] → flex
[display:_flex] → [display:flex] → flex
[display:flex_] → [display:flex] → flex
[display:flex] → [display:flex] → flex
```
If we don't do this, then the signatures will be slightly different, due
to the whitespace:
| UTILITY | GENERATED SIGNATURE |
| ------------------ | ------------------------- |
| `[display:_flex_]` | `.x { display: flex ; }` |
| `[display:_flex]` | `.x { display: flex; }` |
| `[display:flex_]` | `.x { display: flex ; }` |
| `[display:flex]` | `.x { display: flex; }` |
### Other small improvements
A few other improvements are for optimizing existing utilities:
1. Remove unnecessary data types. E.g.:
- `bg-[color:red]` -> `bg-[red]`
- `shadow-[shadow:inset_0_1px_--theme(--color-white/15%)]` ->
`shadow-[inset_0_1px_--theme(--color-white/15%)]`
This also makes use of these signatures and if dropping the data type
results in the same signature then we can safely drop it.
Additionally, if a more specific utility exists, we will prefer that
one. This reduced ambiguity and the need for data types.
- `bg-[position:123px]` → `bg-position-[123px]`
- `bg-[123px]` → `bg-position-[123px]`
- `bg-[size:123px]` → `bg-size-[123px]`
2. Optimizing modifiers. E.g.:
- `bg-red-500/[25%]` → `bg-red-500/25`
- `bg-red-500/[100%]` → `bg-red-500`
- `bg-red-500/100` → `bg-red-500`
3. Hoist `not` in arbitrary variants
- `[@media_not_(prefers-color-scheme:dark)]:flex` →
`not-[@media_(prefers-color-scheme:dark)]:flex` → `not-dark:flex` (in
case you are using the default `dark` mode implementation
4. Optimize raw values that could be converted to bare values. This uses
the `--spacing` variable to ensure it is safe.
- `w-[64rem]` → `w-256`
---------
Co-authored-by: Jordan Pittman <jordan@cryptica.me>
Co-authored-by: Philipp Spiess <hello@philippspiess.com>
This PR improves the upgrade tooling at tiny bit to make sure that as
long as we didn't change any of the stylesheets, that we also don't sort
internal nodes and/or format the stylesheet at all.
This is important in case the Prettier rules are different or if a
totally different formatter is used.
Essentially, if we didn't have to change the stylesheets because of a
migration, we don't want to change it due to a formatter either.
To fix the CI issues we have, it turns out there are two issues:
1. The file-read was not retried, making it possible for all platforms
(but mostly Windows because it's the slowest) to sometimes not have the
file created yet before making the assertion.
2. A forward-slash in the assertion message path would always be a
backslash when run on Windows, thus the Windows test would never pass.
## Test plan
- [ci-all] and have the test pass two times.
Closes#17295
This commit addresses an issue where the PostCSS plugin would get stuck
in an error state when processing files with e.g. invalid @apply
directives.
This change prevents the PostCSS plugin from getting stuck in an error
states particularly when the error happened inside an `@import`ed CSS
files (as these were not registered as dependencies correctly before).
## Error overlays
Some frameworks (e.g. Angular 19 or Next.js) handle errors inside
PostCSS transforms to render a nice error overlay. This works well and
gives immediate feedback that something went wrong. However, even when
dependencies are registered before an error is thrown, these frameworks
_will not consider changes to these dependencies anymore_ when an error
occurs, as you can see in this Next.js example:
https://github.com/user-attachments/assets/985c9dd7-daf8-4628-b4ad-6543ef220954
To avoid conditions where errors are not recoverable, this PR makes it
so that these overlays will no longer show up in the app and only be
logged to the output console. This will need follow-up upstream work
before we can revisit this.
## Test plan
- Tested with the repro in #17295. The error can now be recovered from.
- Tested with a Next.js app where the issue in the screencast above is
now no longer happening.
- Added an integration test for errors in `@import`-ed files
- Added a unit test for the changed `@apply` behavior.
This PR ensures that the `@tailwindcss/upgrade` tool works on existing
Tailwind CSS v4 projects. This PR also ensures that the upgrade tool is
idempotent, meaning that it can be run multiple times and it should
result in the same output.
One awesome feature this unlocks is that you can run the upgrade tool on
your codebase at any time and upgrade classes if you still have some
legacy syntaxes, such as `bg-[var(--my-color)]`, in your muscle memory.
One small note: If something changed in the first run, re-running will
not work immediately because your git repository will not be clean and
the upgrade tool requires your git repo to be clean. But once you
verified and committed your changes, the upgrade tool will be
idempotent.
Idempotency is guaranteed by ensuring that some migrations are skipped
by checking what version of Tailwind CSS you are on _before_ the version
is upgraded.
For the Tailwind CSS version: We will resolve `tailwindcss` itself to
know the _actual_ version that is installed (the one resolved from
`node_modules`). Not the one available in your package.json. Your
`package.json` could be out of sync if you reverted changes but didn't
run `npm install` yet.
Back to Idempotency:
For example, we have migrations where we change the variant order of
stacked variants. If we would run these migrations every time you run
the upgrade tool then we would be flip-flopping the order every run.
See: https://tailwindcss.com/docs/upgrade-guide#variant-stacking-order
Another example is where we rename some utilities. For example, we
rename:
| Before | After |
| ----------- | ----------- |
| `shadow` | `shadow-sm` |
| `shadow-sm` | `shadow-xs` |
Notice how we have `shadow-sm` in both the `before` and `after` column.
If we would run the upgrade tool again, then we would eventually migrate
your original `shadow` to `shadow-sm` (first run) and then to
`shadow-xs` (second run). Which would result in the wrong shadow.
See: https://tailwindcss.com/docs/upgrade-guide#renamed-utilities
---
The order of upgrade steps changed a bit as well to make the internals
are easier to work with and reason about.
1. Find CSS files
2. Link JS config files (if you are in a Tailwind CSS v3 project)
3. Migrate the JS config files (if you are in a Tailwind CSS v3 project)
4. Upgrade Tailwind CSS to v4 (or the latest version at that point)
5. Migrate the stylesheets (we used to migrate the source files first)
6. Migrate the source files
This is done so that step 5 and 6 will always operate on a Tailwind CSS
v4 project and we don't need to check the version number again. This is
also necessary because your CSS file will now very likely contain
`@import "tailwindcss";` which doesn't exist in Tailwind CSS v3.
This also means that we can rely on the same internals that Tailwind CSS
actually uses for locating the source files. We will use
`@tailwindcss/oxide`'s scanner to find the source files (and it also
keeps your custom `@source` directives into account).
This PR also introduces a few actual migrations related to recent
features and changes we shipped.
1. We migrate deprecated classes to their new names:
| Before | After |
| --------------------- | --------------------- |
| `bg-left-top` | `bg-top-left` |
| `bg-left-bottom` | `bg-bottom-left` |
| `bg-right-top` | `bg-top-right` |
| `bg-right-bottom` | `bg-bottom-right` |
| `object-left-top` | `object-top-left` |
| `object-left-bottom` | `object-bottom-left` |
| `object-right-top` | `object-top-right` |
| `object-right-bottom` | `object-bottom-right` |
Introduced in:
- https://github.com/tailwindlabs/tailwindcss/pull/17378
- https://github.com/tailwindlabs/tailwindcss/pull/17437
2. We migrate simple arbitrary variants to their dedicated variant:
| Before | After |
| ----------------------- | ------------------- |
| `[&:user-valid]:flex` | `user-valid:flex` |
| `[&:user-invalid]:flex` | `user-invalid:flex` |
Introduced in:
- https://github.com/tailwindlabs/tailwindcss/pull/12370
3. We migrate `@media` variants to their dedicated variant:
| Before | After |
| ----------------------------------------------------- |
------------------------- |
| `[@media_print]:flex` | `print:flex` |
| `[@media(prefers-reduced-motion:no-preference)]:flex` |
`motion-safe:flex` |
| `[@media(prefers-reduced-motion:reduce)]:flex` | `motion-reduce:flex`
|
| `[@media(prefers-contrast:more)]:flex` | `contrast-more:flex` |
| `[@media(prefers-contrast:less)]:flex` | `contrast-less:flex` |
| `[@media(orientation:portrait)]:flex` | `portrait:flex` |
| `[@media(orientation:landscape)]:flex` | `landscape:flex` |
| `[@media(forced-colors:active)]:flex` | `forced-colors:flex` |
| `[@media(inverted-colors:inverted)]:flex` | `inverted-colors:flex` |
| `[@media(pointer:none)]:flex` | `pointer-none:flex` |
| `[@media(pointer:coarse)]:flex` | `pointer-coarse:flex` |
| `[@media(pointer:fine)]:flex` | `pointer-fine:flex` |
| `[@media(any-pointer:none)]:flex` | `any-pointer-none:flex` |
| `[@media(any-pointer:coarse)]:flex` | `any-pointer-coarse:flex` |
| `[@media(any-pointer:fine)]:flex` | `any-pointer-fine:flex` |
| `[@media(scripting:none)]:flex` | `noscript:flex` |
The new variants related to `inverted-colors`, `pointer`, `any-pointer`
and `scripting` were introduced in:
- https://github.com/tailwindlabs/tailwindcss/pull/11693
- https://github.com/tailwindlabs/tailwindcss/pull/16946
- https://github.com/tailwindlabs/tailwindcss/pull/11929
- https://github.com/tailwindlabs/tailwindcss/pull/17431
This also applies to the `not` case, e.g.:
| Before | After |
| --------------------------------------------------------- |
----------------------------- |
| `[@media_not_print]:flex` | `not-print:flex` |
| `[@media_not(prefers-reduced-motion:no-preference)]:flex` |
`not-motion-safe:flex` |
| `[@media_not(prefers-reduced-motion:reduce)]:flex` |
`not-motion-reduce:flex` |
| `[@media_not(prefers-contrast:more)]:flex` | `not-contrast-more:flex`
|
| `[@media_not(prefers-contrast:less)]:flex` | `not-contrast-less:flex`
|
| `[@media_not(orientation:portrait)]:flex` | `not-portrait:flex` |
| `[@media_not(orientation:landscape)]:flex` | `not-landscape:flex` |
| `[@media_not(forced-colors:active)]:flex` | `not-forced-colors:flex` |
| `[@media_not(inverted-colors:inverted)]:flex` |
`not-inverted-colors:flex` |
| `[@media_not(pointer:none)]:flex` | `not-pointer-none:flex` |
| `[@media_not(pointer:coarse)]:flex` | `not-pointer-coarse:flex` |
| `[@media_not(pointer:fine)]:flex` | `not-pointer-fine:flex` |
| `[@media_not(any-pointer:none)]:flex` | `not-any-pointer-none:flex` |
| `[@media_not(any-pointer:coarse)]:flex` |
`not-any-pointer-coarse:flex` |
| `[@media_not(any-pointer:fine)]:flex` | `not-any-pointer-fine:flex` |
| `[@media_not(scripting:none)]:flex` | `not-noscript:flex` |
For each candidate, we run a set of upgrade migrations. If at the end of
the migrations the original candidate is still the same as the new
candidate, then we will parse & print the candidate one more time to
pretty print into consistent classes. Luckily parsing is cached so there
is no real downside overhead.
Consistency (especially with arbitrary variants and values) will reduce
your CSS file because there will be fewer "versions" of your class.
Concretely, the pretty printing will apply changes such as:
| Before | After |
| ---------------------- | ----------------- |
| `bg-[var(--my-color)]` | `bg-(--my-color)` |
| `bg-[rgb(0,_0,_0)]` | `bg-[rgb(0,0,0)]` |
Another big important reason for this change is that these classes on
their own
would have been migrated _if_ another migration was relevant for this
candidate.
This means that there are were some inconsistencies. E.g.:
| Before | After | Reason |
| ----------------------- | ---------------------- |
------------------------------------ |
| `!bg-[var(--my-color)]` | `bg-(--my-color)!` | Because the `!` is in
the wrong spot |
| `bg-[var(--my-color)]` | `bg-[var(--my-color)]` | Because no
migrations rand |
As you can see, the way the `--my-color` variable is used, is different.
This
changes will make sure it will now always be consistent:
| Before | After |
| ----------------------- | ---------------------- |
| `!bg-[var(--my-color)]` | `bg-(--my-color)!` |
| `bg-[var(--my-color)]` | `bg-(--my-color)` |
Yay!
Of course, if you don't want these more cosmetic changes, you can always
ignore the upgrade and revert these changes and only commit the changes
you want.
# Test plan
- All existing tests still pass.
- But I had to delete 1 test (we tested that Tailwind CSS v3 was
required).
- And had to mock the `version.isMajor` call to ensure we run the
individual migration tests correctly.
- Added new tests to test:
1. Migrating Tailwind CSS v4 projects works
1. Idempotency of the upgrade tool
[ci-all]
Closes#17448Closes#13133
This PR adds an a new Oxide target for `wasm32-wasip1-threads`:
`@tailwindcss/oxide-wasm32-wasi`. The goal of this is to enable more
environments to run Oxide, including (but not limited to) StackBlitz.
We're making use of `napi-rs`'s upcoming v3 features to simplify the
setup here, meaning `napi-rs` will configure the WASM target and create
an npm package that works across Node and browser environments.
## MacOS AArch64 issues
While setting up an integration test for the new WASM target, I ran into
an issue where FS reads where not terminating on macOS. After some
research I found this to be a limitation of the Node.js container
interface right now, see: https://github.com/nodejs/node/issues/47193
### Windows issues
We also found that the Node.js wasi container does not properly support
Windows: https://github.com/nodejs/uvwasi/issues/11
For now we, it's probably best for MacOS AArch64 users and Windows users
to use the native modules instead.
## Test plan
The `@tailwindcss/oxide-wasm32-wasi` npm package can be built locally
via `pnpm build` and then run with the Oxide API. A usage example can be
taken from the newly added integration test.
Furthermore this was tested to work as a polyfill on StackBlitz:
https://stackblitz.com/edit/vitejs-vite-uks3gt5p
[ci-all]
---------
Co-authored-by: Robin Malfait <malfait.robin@gmail.com>
Fixes#17622.
Adds a specific handling case in `themeableValues()` in
`packages/tailwindcss/src/compat/apply-config-to-theme.ts`. It seems
like this has unique handling in v3 for an array value, whereby the
second value is treated as a `line-height`.
---------
Co-authored-by: Philipp Spiess <hello@philippspiess.com>
Closes#17512
One of the changes of the Oxide API in 4.1 is that it now emits the
input CSS file itself as a dependency. This was fine in most of our
testing but it turns out that certain integrations (in this case a Qwik
project) don't like this and will silently crash with no CSS file being
added anymore.
This PR fixes this by making sure we don't add the input file as a
dependency on itself and also adds an integration test to ensure this
won't regress again.
## Test plan
- Tested with the repro provided in #17512
- Added a minimal integration test based on that reproduction that I
also validated will _fail_, if the fix is reverted.
This PR further improves the `color-mix(…)` polyfill to create a
reasonable fallback if dynamic values that can not statically be
resolved are used. This refers to either the use of `currentcolor` or
any variables that are not static theme variables.
Here are two examples that now generate a reasonable fallback instead of
not showing any color at all:
```css
.text-\\(--my-color\\)\\/\\(--my-opacity\\) {
color: var(--my-color);
}
@supports (color: color-mix(in lab, red, red)) {
.text-\\(--my-color\\)\\/\\(--my-opacity\\) {
color: color-mix(in oklab, var(--my-color) var(--my-opacity), transparent);
}
}
```
```css
.text-current\\/50 {
color: currentColor;
}
@supports (color: color-mix(in lab, red, red)) {
.text-current\\/50 {
color: color-mix(in oklab, currentColor 50%, transparent);
}
}
```
## Test plan
- Made sure the test diffs are looking reasonable
- Tested this on a production site with `<p className="text-shadow-lg/50
[--my-color:red] text-shadow-(color:--my-color)">shadow test</p>`
- Browsers that do not support `color-mix(…)` will properly show a red
shadow now albeit with 100% opacity: iOS 15.5 and Chrome 110
- Browsers that I have tested to make sure it still works there with
opacity: Firefox 127, Firefox 128, Latest Chrome, Safari, Firefox
- Browsers that do show a black shadow because of `var(…)var(…)` being
chained with no space by lightningcss: Chrome 111
This PR fixes an issue where if you use Next.js with `--turbopack` a
race condition happens because the `@tailwindcss/postcss` plugin is
called twice in rapid succession.
The first call sees an update and does a partial update with the new
classes. Next some internal `mtimes` are updated. The second call
therefore doesn't see any changes anymore because the `mtimes` are the
same, therefore it's serving its stale data.
Fixes: #17508
## Test plan
- Tested with the repro provided in #17508
- Added a new unit test that calls into the PostCSS plugin directly for
the same change from the same JavaScript run-loop.
---------
Co-authored-by: Philipp Spiess <hello@philippspiess.com>
This PR changes how polyfills for `@property` are inserted. The main
motivation is to remove the need to rely on the correct placement of
`@layer base;`—Something that's not really required right not in
Tailwind CSS v4 and we'd like to keep it this way.
The idea is that the polyfills are inserted for you automatically. To
ensure they always take precedence, we insert an empty `@layer
properties;` at the top of the CSS file so that later, when we emit all
`@property` rules and their fallback, we can use this new named layer to
ensure the rules have a higher order.
Unfortunately, just putting `@layer properties;` at the beginning of a
file would not work as `lightningcss` incorrectly hoists all content
into the first occurrence of a layer name meaning these rules might be
inserted _before_ eventual external imports:
To work around this, we have to insert that layer name after any
eventual remaining external `@imports` for now.
## Test plan
- Updated snapshot tests
- Deployed a new version of the website with the patch applied to ensure
it works across browsers:
https://tailwindcss-com-git-legacy-browsers-tailwindlabs.vercel.app/.
Tested on: Safari on iOS 15.5, Safari on iOS 16.0, Firefox 127, Firefox
128, Chrome 110, Chrome latest, Safari latest, Firefox latest
This PR fixes an issue where polyfills were injected at the top, but
they should be after `@import` and body-less `@layer` rules.
This is necessary in case you are using Google fonts like this for
example:
```css
@import url('https://fonts.google.com');
@import "tailwindcss";
```
While the `@import url(…);` sits above `@import "tailwindcss";` in the
final generated CSS we injected the polyfills at the very beginning.
This PR will inject the polyfills after the first AST Node that is not:
1. A comment
2. An external import — `@import url(…)`
3. A body-less layer — `@layer foo, bar, baz;`
The snapshots look a little confusing, but that's because Lightning CSS
is optimizing the output and moving things around a bit:
<img width="1482" alt="image"
src="https://github.com/user-attachments/assets/a0552c8b-93df-4e1d-ad90-8b8abf9492b1"
/>
[Lightning CSS
Playground](https://lightningcss.dev/playground/index.html#%7B%22minify%22%3Afalse%2C%22customMedia%22%3Atrue%2C%22cssModules%22%3Afalse%2C%22analyzeDependencies%22%3Afalse%2C%22targets%22%3A%7B%22chrome%22%3A6225920%7D%2C%22include%22%3A0%2C%22exclude%22%3A0%2C%22source%22%3A%22%40layer%20theme%2C%20base%2C%20components%2C%20utilities%3B%5Cn%5Cn%40supports%20(((-webkit-hyphens%3A%20none))%20and%20(not%20(margin-trim%3A%20inline)))%20or%20((-moz-orient%3A%20inline)%20and%20(not%20(color%3A%20rgb(from%20red%20r%20g%20b))))%20%7B%5Cn%20%20%40layer%20base%20%7B%5Cn%20%20%20%20*%2C%20%3Abefore%2C%20%3Aafter%2C%20%3A%3Abackdrop%20%7B%5Cn%20%20%20%20%20%20--tw-font-weight%3A%20initial%3B%5Cn%20%20%20%20%7D%5Cn%20%20%7D%5Cn%7D%5Cn%5Cn%40layer%20theme%20%7B%5Cn%20%20%3Aroot%2C%20%3Ahost%20%7B%5Cn%20%20%20%20--font-sans%3A%20ui-sans-serif%2C%20system-ui%2C%20sans-serif%2C%20%5C%22Apple%20Color%20Emoji%5C%22%2C%20%5C%22Segoe%20UI%20Emoji%5C%22%2C%20%5C%22Segoe%20UI%20Symbol%5C%22%2C%20%5C%22Noto%20Color%20Emoji%5C%22%3B%5Cn%20%20%20%20--font-mono%3A%20ui-monospace%2C%20SFMono-Regular%2C%20Menlo%2C%20Monaco%2C%20Consolas%2C%20%5C%22Liberation%20Mono%5C%22%2C%20%5C%22Courier%20New%5C%22%2C%20monospace%3B%5Cn%20%20%20%5Cn%20%20%7D%5Cn%7D%5Cn%5Cn%40layer%20base%20%7B%5Cn%20%20*%2C%20%3Aafter%2C%20%3Abefore%2C%20%3A%3Abackdrop%20%7B%5Cn%20%20%20%20box-sizing%3A%20border-box%3B%5Cn%20%20%20%20border%3A%200%20solid%3B%5Cn%20%20%20%20margin%3A%200%3B%5Cn%20%20%20%20padding%3A%200%3B%5Cn%20%20%7D%5Cn%7D%5Cn%5Cn%40layer%20utilities%20%7B%5Cn%20%20.text-2xl%20%7B%5Cn%20%20%20%20font-size%3A%20var(--text-2xl)%3B%5Cn%20%20%20%20line-height%3A%20var(--tw-leading%2C%20var(--text-2xl--line-height))%3B%5Cn%20%20%7D%5Cn%7D%5Cn%5Cn%40property%20--tw-font-weight%20%7B%5Cn%20%20syntax%3A%20%5C%22*%5C%22%3B%5Cn%20%20inherits%3A%20false%5Cn%7D%22%2C%22visitorEnabled%22%3Afalse%2C%22visitor%22%3A%22%7B%5Cn%20%20Color(color)%20%7B%5Cn%20%20%20%20if%20(color.type%20%3D%3D%3D%20'rgb')%20%7B%5Cn%20%20%20%20%20%20color.g%20%3D%200%3B%5Cn%20%20%20%20%20%20return%20color%3B%5Cn%20%20%20%20%7D%5Cn%20%20%7D%5Cn%7D%22%2C%22unusedSymbols%22%3A%5B%5D%2C%22version%22%3A%22local%22%7D)
Fixes: #17494
This PR improves the compatibility with Tailwind CSS v4 with unsupported
browsers with the goal to greatly improve compatibility with Safari 15.
To make this work, this PR makes the following changes to all code
- Change `oklab(…)` default theme values to use a percentage in the
first place (so instead of `--color-red-500: oklch(0.637 0.237 25.331);`
we now define it as `--color-red-500: oklch(63.7% 0.237 25.331);` since
this syntax has much broader support on Safari).
- Polyfill `@property` with a `@supports` query targeting older versions
of Safari and Firefox *
- Create fallbacks for the `color-mix(…)` function that use _inlined
color values from your theme_ so that they can be computed a compile
time by `lightningcss`. These fallbacks will convert to srgb to increase
compatibility.
- Create fallbacks for the _relative color_ feature used in the new
shadow utilities and using `color-mix(…)` in case _relative color_ is
applied on `currentcolor` (due to limited browser support)
- Create fallbacks for gradient interpolation methods (e.g. to support
`bg-linear-to-r/oklab`)
- Polyfill `@media` queries range syntax.
## A simplified example
Given this example CSS input:
```css
@import 'tailwindcss';
@source inline('from-cyan-500/50 bg-linear-45');
```
Here's the updated output CSS including the newly added polyfills and
updated `oklab` values:
```css
.bg-linear-45 {
--tw-gradient-position: 45deg;
background-image: linear-gradient(var(--tw-gradient-stops));
}
@supports (background-image: linear-gradient(in lab, red, red)) {
.bg-linear-45 {
--tw-gradient-position: 45deg in oklab;
}
}
.from-cyan-500\\/50 {
--tw-gradient-from: oklab(71.5% -.11682 -.08247 / .5);
--tw-gradient-stops: var(--tw-gradient-via-stops, var(--tw-gradient-position), var(--tw-gradient-from) var(--tw-gradient-from-position), var(--tw-gradient-to) var(--tw-gradient-to-position));
}
@supports (color: color-mix(in lab, red, red)) {
.from-cyan-500\\/50 {
--tw-gradient-from: color-mix(in oklab, var(--color-cyan-500) 50%, transparent);
}
}
:root, :host {
--color-cyan-500: oklch(71.5% .143 215.221);
}
@supports (((-webkit-hyphens: none)) and (not (margin-trim: 1lh))) or ((-moz-orient: inline) and (not (color: rgb(from red r g b)))) {
@layer base {
*, :before, :after, ::backdrop {
--tw-gradient-position: initial;
--tw-gradient-from: #0000;
--tw-gradient-via: #0000;
--tw-gradient-to: #0000;
--tw-gradient-stops: initial;
--tw-gradient-via-stops: initial;
--tw-gradient-from-position: 0%;
--tw-gradient-via-position: 50%;
--tw-gradient-to-position: 100%;
}
}
}
@property --tw-gradient-position {
syntax: "*";
inherits: false
}
@property --tw-gradient-from {
syntax: "<color>";
inherits: false;
initial-value: #0000;
}
@property --tw-gradient-via {
syntax: "<color>";
inherits: false;
initial-value: #0000;
}
@property --tw-gradient-to {
syntax: "<color>";
inherits: false;
initial-value: #0000;
}
@property --tw-gradient-stops {
syntax: "*";
inherits: false
}
@property --tw-gradient-via-stops {
syntax: "*";
inherits: false
}
@property --tw-gradient-from-position {
syntax: "<length-percentage>";
inherits: false;
initial-value: 0%;
}
@property --tw-gradient-via-position {
syntax: "<length-percentage>";
inherits: false;
initial-value: 50%;
}
@property --tw-gradient-to-position {
syntax: "<length-percentage>";
inherits: false;
initial-value: 100%;
}
```
## \* A note on `@property` polyfills and CSS modules
On Next.js, CSS module files are required to be _pure_, meaning that all
selectors must either be scoped to a class or an ID. Fortunatnyl for us,
this does not apply to `@property` rules which we've been using before
to initialize CSS variables.
However, since we're now bringing back the `@property` polyfills, that
would cause unexpected rules to be exported from the CSS file as this:
```css
@reference "tailwindcss";
.skew {
@apply skew-7;
}
```
Would turn to the following file:
```css
.skew {
/* … */
}
@supports (/*…*/) {
@layer base {
*, :before, :after, ::backdrop {
--tw-gradient-position: initial;
}
}
}
@property /* … */
```
Notice that this adds a `*` selector which is not considered pure.
Unfortunately there is no way for us to silence this warning or work
around it, as the dependency causing this errors
([`postcss-modules-local-by-default`](https://github.com/css-modules/postcss-modules-local-by-default))
is bundled into Next.js. To work around crashes, these polyfills will
not apply to CSS modules processed by the PostCSS extension for now.
## Testing on tailwindcss.com
To see the changes in effect, take a look at this screencast that
compares tailwindcss.com on iOS 15.5 with a version that has the patches
of this PR applied:
https://github.com/user-attachments/assets/1279d6f5-3c63-4f30-839c-198a789f4292
## Test plan
- Tested on tailwindcss.com via a preview build:
https://tailwindcss-com-git-legacy-browsers-tailwindlabs.vercel.app/
- Updated tests
- Ensure we also test on Chrome 111, Safari 16.4, Firefox 128 to
make sure we have no regressions. Also tested on Safari 16.4, 15.5, 18.0
This PR will fix CI on the main branch where `webpack` could not be
found on macOS (but it worked on Linux).
Going to run [ci-all] to verify the changes.
This PR is a follow-up PR for:
https://github.com/tailwindlabs/tailwindcss/pull/17433
In the other PR we allow scanning CSS files for extracting usages of CSS
variables. This is important for `.module.css` files that reference
these variables but aren't in the same big AST of the main CSS file.
This PR also makes sure to watch for changes in those registered CSS
files and re-extract the variables when they change.
This PR took a bit longer than expected because I was trying to make
sure that writing to `./dist/out.css` works without infinite-looping
(e.g.: we had issues with this in Tailwind CSS v3 with webpack).
But I couldn't reproduce the issue at all. I did had some code that
tried to detect if the CSS file contained license headers and skip in
(because then it's very likely an output CSS file) but even without it
the tests were fine.
I setup integration tests with `@tailwindcss/cli` itself, and with tools
that use webpack. Added a test for Next.js, and a dedicated webpack test
as well.
Even without tests, locally, I couldn't reproduce an infinite loop due
to changes in an output CSS file...
Eventually dropped the code that tries to detect output CSS files.
One thing to keep in mind is that if you change any of your "main" CSS
files, then we will trigger a full rebuild anyway, so this change is
only required for unrelated CSS files (like CSS module files) that use
CSS variables.
## Test plan
1. Added integration tests for the CLI and Next.js
2. Added new dedicated test for webpack
This PR adds a new source detection feature: `@source not "…"`. It can
be used to exclude files specifically from your source configuration
without having to think about creating a rule that matches all but the
requested file:
```css
@import "tailwindcss";
@source not "../src/my-tailwind-js-plugin.js";
```
While working on this feature, we noticed that there are multiple places
with different heuristics we used to scan the file system. These are:
- Auto source detection (so the default configuration or an `@source
"./my-dir"`)
- Custom sources ( e.g. `@source "./**/*.bin"` — these contain file
extensions)
- The code to detect updates on the file system
Because of the different heuristics, we were able to construct failing
cases (e.g. when you create a new file into `my-dir` that would be
thrown out by auto-source detection, it'd would actually be scanned). We
were also leaving a lot of performance on the table as the file system
is traversed multiple times for certain problems.
To resolve these issues, we're now unifying all of these systems into
one `ignore` crate walker setup. We also implemented features like
auto-source-detection and the `not` flag as additional _gitignore_ rules
only, avoid the need for a lot of custom code needed to make decisions.
High level, this is what happens after the now:
- We collect all non-negative `@source` rules into a list of _roots_
(that is the source directory for this rule) and optional _globs_ (that
is the actual rules for files in this file). For custom sources (i.e
with a custom `glob`), we add an allowlist rule to the gitignore setup,
so that we can be sure these files are always included.
- For every negative `@source` rule, we create respective ignore rules.
- Furthermore we have a custom filter that ensures files are only read
if they have been changed since the last time they were read.
So, consider the following setup:
```css
/* packages/web/src/index.css */
@import "tailwindcss";
@source "../../lib/ui/**/*.bin";
@source not "../../lib/ui/expensive.bin";
```
This creates a git ignore file that (simplified) looks like this:
```gitignore
# Auto-source rules
*.{exe,node,bin,…}
*.{css,scss,sass,…}
{node_modules,git}/
# Custom sources can overwrite auto-source rules
!lib/ui/**/*.bin
# Negative rules
lib/ui/expensive.bin
```
We then use this information _on top of your existing `.gitignore`
setup_ to resolve files (i.e so if your `.gitignore` contains rules e.g.
`dist/` this line is going to be added _before_ any of the rules lined
out in the example above. This allows negative rules to allow-list your
`.gitignore` rules.
To implement this, we're rely on the `ignore` crate but we had to make
various changes, very specific, to it so we decided to fork the crate.
All changes are prefixed with a `// CHANGED:` block but here are the
most-important ones:
- We added a way to add custom ignore rules that _extend_ (rather than
overwrite) your existing `.gitignore` rules
- We updated the order in which files are resolved and made it so that
more-specific files can allow-list more generic ignore rules.
- We resolved various issues related to adding more than one base path
to the traversal and ensured it works consistent for Linux, macOS, and
Windows.
## Behavioral changes
1. Any custom glob defined via `@source` now wins over your `.gitignore`
file and the auto-content rules.
- Resolves#16920
3. The `node_modules` and `.git` folders as well as the `.gitignore`
file are now ignored by default (but can be overridden by an explicit
`@source` rule).
- Resolves#17318
- Resolves#15882
4. Source paths into ignored-by-default folders (like `node_modules`)
now also win over your `.gitignore` configuration and auto-content
rules.
- Resolves#16669
5. Introduced `@source not "…"` to negate any previous rules.
- Resolves#17058
6. Negative `content` rules in your legacy JavaScript configuration
(e.g. `content: ['!./src']`) now work with v4.
- Resolves#15943
7. The order of `@source` definitions matter now, because you can
technically include or negate previous rules. This is similar to your
`.gitingore` file.
9. Rebuilds in watch mode now take the `@source` configuration into
account
- Resolves#15684
## Combining with other features
Note that the `not` flag is also already compatible with [`@source
inline(…)`](https://github.com/tailwindlabs/tailwindcss/pull/17147)
added in an earlier commit:
```css
@import "tailwindcss";
@source not inline("container");
```
## Test plan
- We added a bunch of oxide unit tests to ensure that the right files
are scanned
- We updated the existing integration tests with new `@source not "…"`
specific examples and updated the existing tests to match the subtle
behavior changes
- We also added a new special tag `[ci-all]` that, when added to the
description of a PR, causes the PR to run unit and integration tests on
all operating systems.
[ci-all]
---------
Co-authored-by: Philipp Spiess <hello@philippspiess.com>
Throw an error if the input and output file for the CLI are identical.
---------
Co-authored-by: Philipp Spiess <hello@philippspiess.com>
Co-authored-by: Robin Malfait <malfait.robin@gmail.com>
Closes#17339
This PR fixes an issue that caused changes to `@import`-ed CSS files to
no longer rebuild the stylesheet after a change was made to a template
file.
The change in the template file causes a fast-path in the Vite plugin
now after changes in 4.0.8: _partial rebuilds_. For that branch we do
not need to re-evaluate your input CSS since we know only the candidate
list changed. However, we still need to emit all build dependencies as
via `addWatchFile(…)`, otherwise Vite will not correctly register
updates for these dependencies anymore.
## Test plan
- Updated the kitchen-sink Vite update tests to ensure that an
`@import`-ed CSS file can be updated even after a partial rebuild.
- Ensure this works in our Vite playground
Fixes#17288
This PR fixes an issue where changes in template files that _only mark a
new CSS variable as used_ was not causing the CSS file to rebuilds.
This also fixes a flaky integration test that was caused by a missing
`await` line on the final assertion (causing it to sometimes run the
assertion in time while the test runner was still running).
## Test plan
Turns out we already had an integration test for this but it wasn't
correctly running due to the missing await.
When Tailwind is loaded in a Node Worker thread, it currently causes a
segmentation fault on Linux when the thread exits. This is due to a
longstanding issue in Rust that affects all native modules:
https://github.com/rust-lang/rust/issues/91979. I reported this years
ago but unfortunately it is still not fixed, and seems to have gotten
worse in Rust 1.83.0 and later. Looks like Tailwind recently updated
Rust versions and this issue started appearing when run in tools like
Parcel that use worker threads.
The workaround is to prevent the native module from ever being unloaded.
One way to do that is to always load the native module in the main
thread in addition to workers, but this is hard to enforce.
@Brooooooklyn found another method, which is to use a linker option for
this. I tested this on an Ubuntu system and verified it fixed the issue.
You can test with the following script.
```js
// test.js
const {Worker} = require('worker_threads');
new Worker('./worker.js');
// worker.js
require('@tailwindcss/oxide');
```
Without this change, a segmentation fault will occur.
---------
Co-authored-by: Jordan Pittman <jordan@cryptica.me>
Closes#17194
This PR works around a crash when rendering opacity on `currentColor`
(as used by the placeholder styles in preflight) on Safari 16.4 and
Safari 16.5. Unfortunately it seems that the [`color-mix(…)` function is
not compatible with `currentColor` for these versions of
Safari](https://stackoverflow.com/questions/76436497/the-color-mix-property-involving-currentcolor-causes-safari-to-crash).
We tried a few different ways to work around this without success:
- Using an `@supports` media query to target these Safari versions and
overwriting the placeholder still makes these browsers crash.
- Changing the way we apply opacity to `currentColor` in core doesn't
seem to work for non-placeholder values:
https://github.com/tailwindlabs/tailwindcss/issues/17194#issuecomment-2728949181
However, a wrong opacity is still better than a complete browser crash.
The work-around of using the `oklab(…)` function does seem to work for
`::placeholder` styles in preflight though according to our testing so
this PR applies this change to preflight.
## Test plan
- See https://play.tailwindcss.com/WSsSTLHu8h?file=css
- Tested on Chrome/Safari 16.4/Safari 18.3/Firefox
<img width="564" alt="Screenshot 2025-03-17 at 11 32 47"
src="https://github.com/user-attachments/assets/cfd0db71-f39a-4bc0-bade-cea70afe50ae"
/>
Fixes#16636
This PR enables URL rebasing for PostCSS. Furthermore it fixes an issue
where transitive imports rebased against the importer CSS file instead
of the input CSS file. While fixing this we noticed that this is also
broken in Vite right now and that our integration test swallowed that
when testing because it did not import any Tailwind CSS code and thus
was not considered a Tailwind file.
## Test plan
- Added regression integration tests
- Also validated it against the repro of
https://github.com/tailwindlabs/tailwindcss/issues/16962:
<img width="1149" alt="Screenshot 2025-03-05 at 16 41 01"
src="https://github.com/user-attachments/assets/85396659-d3d0-48c0-b1c7-6125ff8e73ac"
/>
---------
Co-authored-by: Robin Malfait <malfait.robin@gmail.com>
Co-authored-by: Jordan Pittman <jordan@cryptica.me>
This PR ensures we bundle the relevant JS APIs in the Standalone CLI
like `tailwindcss`, `tailwindcss/plugin`, `tailwindcss/colors`, etc…
Before, when loading plugins or configs, imports for those resources
would fail.
Fixes#15235
---------
Co-authored-by: Philipp Spiess <hello@philippspiess.com>
Fixes#16725
When using `@reference "tailwindcss";` inside a separate CSS root (e.g.
Svelte `<style>` components, CSS modules, etc.), we have no guarantee
that the CSS variables will be defined in the main stylesheet (or if
there even is one). To work around potential issues with this we decided
in #16676 that we would emit all used CSS variables from the `@theme`
inside the `@reference` block.
However, this is not only a bit surprising but also unexpected in CSS
modules and Next.js that **requires CSS module files to only create
scope-able declarations**. To fix this issue, we decided to not emit CSS
variables but instead ensure all `var(…)` calls we create for theme
values in reference mode will simply have their fallback value added.
This ensures styles work as-expected even if the root Tailwind file does
not pick up the variable as being used or _if you don't add a root at
all_. Furthermore we do not duplicate any variable declarations across
your stylesheets and you still have the ability to change variables at
runtime.
## Test plan
- Updated snapshots everywhere (see diff)
- New Next.js CSS modules integration test
Fixes#16732
If we can not get the mtime from a file, chances are that the resource
is a virtual module. This is perfectly legit and we can fall back to
what we did before the changes in `4.0.8` (which is to rebuild the root
every time a change contains a dependency like that).
## Test plan
Added a test to mimic the setup from the repor in #16732. Also ensured
the repro now passes:
<img width="1278" alt="Screenshot 2025-02-24 at 17 29 38"
src="https://github.com/user-attachments/assets/d111273d-579f-44c2-82f5-aa32d6a1879a"
/>
Note that importing virtual modules directly in CSS does not work as the
resolver we use does not resolve against the Vite runtime it seems. This
is unrelated to the regression added in `4.0.8` though and something to
look into in the future.
Right now we sort the nodes based on a pre-defined sort order based on
the properties that are being used. The property sort order is defined
in a list we maintain.
We also have to make sure that the property count is taken into account
such that if all the "sorts" are the same, that we fallback to the
property count. Most amount of properties should be first such that we
can override it with more specific utilities that have fewer properties.
However, if a property doesn't exist, then it wouldn't be included in a
list of properties therefore the total count was off.
This PR fixes that by counting all the used properties. If a property
already exists it is counted twice. E.g.:
```css
.foo {
color: red;
&:hover {
color: blue;
}
}
```
In this case, we have 2 properties, not 1 even though it's the same
`color` property.
## Test plan:
1. Updated the tests that are now sorted correctly
2. Added an integration test to make sure that `prose-invert` is defined
after the `prose-stone` classes when using the `@tailwindcss/typography`
plugin where this problem originated from.
Note how in this play (https://play.tailwindcss.com/wt3LYDaljN) the
`prose-invert` comes _before_ the `prose-stone` which means that you
can't apply the `prose-invert` classes to invert `prose-stone`.
