Add details-content variant

This matches the new `::details-content` pseudo element.

Author: lukewarlow

CHANGELOG.md

@@ -7,7 +7,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
-- Nothing yet
+### Added
+
+- Target `::details-content` in new `details-content` variant ([#15319](https://github.com/tailwindlabs/tailwindcss/pull/15319))
 
 ## [4.0.0] - 2025-01-21
 ## [4.0.0-beta.10] - 2025-01-21

packages/tailwindcss/src/__snapshots__/intellisense.test.ts.snap

@@ -7749,6 +7749,13 @@ exports[`getVariants 1`] = `
     "selectors": [Function],
     "values": [],
   },
+  {
+    "hasDash": true,
+    "isArbitrary": false,
+    "name": "details-content",
+    "selectors": [Function],
+    "values": [],
+  },
   {
     "hasDash": true,
     "isArbitrary": false,

packages/tailwindcss/src/variants.test.ts

@@ -104,6 +104,15 @@ test('backdrop', async () => {
   expect(await run(['backdrop/foo:flex'])).toEqual('')
 })
 
+test('details-content', async () => {
+  expect(await run(['details-content:flex'])).toMatchInlineSnapshot(`
+    ".details-content\\:flex::details-content {
+      display: flex;
+    }"
+  `)
+  expect(await run(['details-content/foo:flex'])).toEqual('')
+})
+
 test('before', async () => {
   expect(await run(['before:flex'])).toMatchInlineSnapshot(`
     ".before\\:flex:before {
@@ -2115,6 +2124,7 @@ test('variant order', async () => {
         'data-custom:flex',
         'data-[custom=true]:flex',
         'default:flex',
+        'details-content:flex',
         'disabled:flex',
         'empty:flex',
         'enabled:flex',
@@ -2209,6 +2219,10 @@ test('variant order', async () => {
       display: flex;
     }
 
+    .details-content\\:flex::details-content {
+      display: flex;
+    }
+
     .before\\:flex:before, .after\\:flex:after {
       content: var(--tw-content);
       display: flex;

packages/tailwindcss/src/variants.ts

@@ -628,6 +628,7 @@ export function createVariants(theme: Theme): Variants {
   staticVariant('file', ['&::file-selector-button'])
   staticVariant('placeholder', ['&::placeholder'])
   staticVariant('backdrop', ['&::backdrop'])
+  staticVariant('details-content', ['&::details-content'])
 
   {
     function contentProperties() {