diff --git a/app/package.json b/app/package.json
index cf28739d..bd274b6a 100644
--- a/app/package.json
+++ b/app/package.json
@@ -45,7 +45,7 @@
     "eslint-plugin-react-refresh": "^0.5.0",
     "eslint-plugin-security": "^3.0.1",
     "globals": "^17.3.0",
-    "postcss": "^8.4.30",
+    "postcss": "^8.5.9",
     "tailwindcss": "^4.1.18",
     "typescript": "^5.9.3",
     "typescript-eslint": "^8.9.0",
diff --git a/lib/package.json b/lib/package.json
index c5b6a9fc..3678a60c 100644
--- a/lib/package.json
+++ b/lib/package.json
@@ -75,7 +75,7 @@
     "eslint-plugin-security": "^3.0.1",
     "globals": "^17.3.0",
     "happy-dom": "^20.5.0",
-    "postcss": "^8.4.21",
+    "postcss": "^8.5.9",
     "prettier": "^3.8.1",
     "react": "^18.3.1",
     "react-dom": "^18.3.1",
diff --git a/package-lock.json b/package-lock.json
index 1f61ba53..fe8487cc 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -46,7 +46,7 @@
         "eslint-plugin-react-refresh": "^0.5.0",
         "eslint-plugin-security": "^3.0.1",
         "globals": "^17.3.0",
-        "postcss": "^8.4.30",
+        "postcss": "^8.5.9",
         "tailwindcss": "^4.1.18",
         "typescript": "^5.9.3",
         "typescript-eslint": "^8.9.0",
@@ -196,7 +196,7 @@
         "eslint-plugin-security": "^3.0.1",
         "globals": "^17.3.0",
         "happy-dom": "^20.5.0",
-        "postcss": "^8.4.21",
+        "postcss": "^8.5.9",
         "prettier": "^3.8.1",
         "react": "^18.3.1",
         "react-dom": "^18.3.1",
@@ -12058,9 +12058,9 @@
       }
     },
     "node_modules/postcss": {
-      "version": "8.5.6",
-      "resolved": "https://registry.npmjs.org/postcss/-/postcss-8.5.6.tgz",
-      "integrity": "sha512-3Ybi1tAuwAP9s0r1UQ2J4n5Y0G05bJkpUIO0/bI9MhwmD70S5aTWbXGBwxHrelT+XM1k6dM0pk+SwNkpTRN7Pg==",
+      "version": "8.5.9",
+      "resolved": "https://registry.npmjs.org/postcss/-/postcss-8.5.9.tgz",
+      "integrity": "sha512-7a70Nsot+EMX9fFU3064K/kdHWZqGVY+BADLyXc8Dfv+mTLLVl6JzJpPaCZ2kQL9gIJvKXSLMHhqdRRjwQeFtw==",
       "funding": [
         {
           "type": "opencollective",