Refs #35007 -- Added biome to lint and format CSS files.

5 files changed, 66 insertions, 5 deletions

diff --git a/.editorconfig b/.editorconfig
index f5a029187c..e25596d077 100644
--- a/.editorconfig
+++ b/.editorconfig
@@ -19,13 +19,13 @@ max_line_length = 88
 indent_size = 2
 
 [**/admin/js/vendor/**]
-indent_style = ignore
-indent_size = ignore
+indent_style = unset
+indent_size = unset
 
 # Minified JavaScript files shouldn't be changed
 [**.min.js]
-indent_style = ignore
-insert_final_newline = ignore
+indent_style = unset
+insert_final_newline = unset
 
 # Makefiles always use tabs for indentation
 [Makefile]
diff --git a/.github/workflows/linters.yml b/.github/workflows/linters.yml
index e37d7b5ee2..ccee1adde0 100644
--- a/.github/workflows/linters.yml
+++ b/.github/workflows/linters.yml
@@ -83,3 +83,20 @@ jobs:
         with:
           advanced-security: false
           annotations: true
+
+  biome:
+    runs-on: ubuntu-latest
+    timeout-minutes: 60
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v6
+        with:
+          persist-credentials: false
+      - name: Set up Node.js
+        uses: actions/setup-node@v5
+        with:
+          node-version: '20'
+          cache: 'npm'
+          cache-dependency-path: '**/package.json'
+      - run: npm install
+      - run: npx biome ci
diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index dbe92a2bdc..bc7a5c279a 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -24,6 +24,11 @@ repos:
     rev: v9.39.1
     hooks:
       - id: eslint
+  - repo: https://github.com/biomejs/pre-commit
+    rev: v2.4.12
+    hooks:
+      - id: biome-check
+        additional_dependencies: ["@biomejs/biome@2.4.12"]
   - repo: https://github.com/zizmorcore/zizmor-pre-commit
     rev: v1.19.0
     hooks:
diff --git a/biome.json b/biome.json
new file mode 100644
index 0000000000..cc95757f3e
--- /dev/null
+++ b/biome.json
@@ -0,0 +1,37 @@
+{
+    "$schema": "https://biomejs.dev/schemas/2.4.12/schema.json",
+    "files": {
+        "includes": [
+            "django/contrib/admin/static/admin/css/**/*.css",
+            "!django/contrib/admin/static/admin/css/vendor/**",
+            "django/contrib/gis/static/gis/css/**/*.css",
+            "docs/_theme/**/*.css",
+            "!docs/_theme/djangodocs/static/fontawesome/**",
+            "!docs/_theme/djangodocs/static/reset-fonts-grids.css",
+            "!**/*.min.css"
+        ]
+    },
+    "formatter": {
+        "enabled": true,
+        "useEditorconfig": true
+    },
+    "linter": {
+        "enabled": true,
+        "rules": {
+            "complexity": {
+                "noImportantStyles": "off"
+            },
+            "style": {
+                "noDescendingSpecificity": "off"
+            }
+        }
+    },
+    "javascript": {
+        "linter": { "enabled": false },
+        "formatter": { "enabled": false }
+    },
+    "json": {
+        "linter": { "enabled": false },
+        "formatter": { "enabled": false }
+    }
+}
diff --git a/package.json b/package.json
index a0ae4ad873..e1d22cda11 100644
--- a/package.json
+++ b/package.json
@@ -3,12 +3,14 @@
   "private": true,
   "scripts": {
     "pretest": "eslint .",
-    "test": "grunt test --verbose"
+    "test": "grunt test --verbose",
+    "biome": "biome check"
   },
   "engines": {
     "npm": ">=1.3.0"
   },
   "devDependencies": {
+    "@biomejs/biome": "^2.4.12",
     "eslint": "^9.39.1",
     "puppeteer": "^24.22.0",
     "grunt": "^1.6.1",