diff --git a/config/postcss-config-factory.js b/config/postcss-config-factory.js
index 63932eba584..f70fe25f28b 100644
--- a/config/postcss-config-factory.js
+++ b/config/postcss-config-factory.js
@@ -1,7 +1,6 @@
 import cssnano from 'cssnano';
 import postcssImport from 'postcss-import';
 import postcssModules from 'postcss-modules';
-import postcssNesting from 'postcss-nesting';
 import postcssCSStoESM from '../scripts/postcss-css-to-esm.mjs';
 import cssLayersPlugin from './layers-plugin.js';
 
@@ -9,7 +8,6 @@ export function postcssConfigFactory(packageName) {
   return {
     plugins: [
       postcssImport(),
-      postcssNesting(),
       cssLayersPlugin(),
       postcssModules({
         // generateScopedName: '[name]__[local]___[hash:base64:5]',
diff --git a/package.json b/package.json
index 8fa680545c0..c12af674359 100644
--- a/package.json
+++ b/package.json
@@ -99,7 +99,6 @@
     "postcss-cli": "11.0.1",
     "postcss-import": "16.1.1",
     "postcss-modules": "6.0.1",
-    "postcss-nesting": "14.0.0",
     "prettier": "3.8.1",
     "rimraf": "6.1.3",
     "typescript": "5.7.3",
diff --git a/yarn.lock b/yarn.lock
index c1b3f90b088..24eb465430e 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -1304,24 +1304,6 @@ __metadata:
   languageName: node
   linkType: hard
 
-"@csstools/selector-resolve-nested@npm:^4.0.0":
-  version: 4.0.0
-  resolution: "@csstools/selector-resolve-nested@npm:4.0.0"
-  peerDependencies:
-    postcss-selector-parser: ^7.1.1
-  checksum: 10c0/f6bccfe24a47c3e55710d421740550b868bbe7f0820f32d14d1eb737eefe7ec26261fb726cc5cfdf8236b3173d0a657ebdc9602e0c53824603f719b14a76bcaf
-  languageName: node
-  linkType: hard
-
-"@csstools/selector-specificity@npm:^6.0.0":
-  version: 6.0.0
-  resolution: "@csstools/selector-specificity@npm:6.0.0"
-  peerDependencies:
-    postcss-selector-parser: ^7.1.1
-  checksum: 10c0/7a93973f9054f2e1f03c8543cde68e0b0c65e5e72da6e4e959974d28fe809e11bd2afa1ff2ca11a1690a4c9a2f2bbe00d00e2b07fb2108bf89c5e48fe441c432
-  languageName: node
-  linkType: hard
-
 "@custom-elements-manifest/analyzer@npm:^0.10.10":
   version: 0.10.10
   resolution: "@custom-elements-manifest/analyzer@npm:0.10.10"
@@ -17183,19 +17165,6 @@ __metadata:
   languageName: node
   linkType: hard
 
-"postcss-nesting@npm:14.0.0":
-  version: 14.0.0
-  resolution: "postcss-nesting@npm:14.0.0"
-  dependencies:
-    "@csstools/selector-resolve-nested": "npm:^4.0.0"
-    "@csstools/selector-specificity": "npm:^6.0.0"
-    postcss-selector-parser: "npm:^7.1.1"
-  peerDependencies:
-    postcss: ^8.4
-  checksum: 10c0/ffa1799ed49759be7f09940614a8cfd06f15bd13e01a7eaabf788939c23a6b617ef281ae383f5b3b3078ddd6d78fd90624af164ea5a421698a1b0972cf14253c
-  languageName: node
-  linkType: hard
-
 "postcss-normalize-charset@npm:^7.0.1":
   version: 7.0.1
   resolution: "postcss-normalize-charset@npm:7.0.1"
@@ -20487,7 +20456,6 @@ __metadata:
     postcss-cli: "npm:11.0.1"
     postcss-import: "npm:16.1.1"
     postcss-modules: "npm:6.0.1"
-    postcss-nesting: "npm:14.0.0"
     prettier: "npm:3.8.1"
     react: "npm:19.2.4"
     react-dom: "npm:19.2.4"