diff --git a/packages/prism/package.json b/packages/prism/package.json
index 09de8ae7b..9b54b2d82 100644
--- a/packages/prism/package.json
+++ b/packages/prism/package.json
@@ -36,7 +36,7 @@
     "@types/react": "^18.2.12",
     "param-case": "^4.0.0",
     "postcss": "^8.1.10",
-    "postcss-js": "^3.0.3",
+    "postcss-js": "^5.0.3",
     "react": "^18.1.0",
     "theme-ui": "workspace:^"
   },
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index f6e3d001d..c441d3fc9 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -1095,8 +1095,8 @@ importers:
         specifier: ^8.1.10
         version: 8.4.47
       postcss-js:
-        specifier: ^3.0.3
-        version: 3.0.3
+        specifier: ^5.0.3
+        version: 5.0.3(postcss@8.4.47)
       react:
         specifier: ^18.1.0
         version: 18.3.1
@@ -9744,16 +9744,18 @@ packages:
     peerDependencies:
       postcss: ^8.0.0
 
-  postcss-js@3.0.3:
-    resolution: {integrity: sha512-gWnoWQXKFw65Hk/mi2+WTQTHdPD5UJdDXZmX073EY/B3BWnYjO4F4t0VneTCnCGQ5E5GsCdMkzPaTXwl3r5dJw==}
-    engines: {node: '>=10.0'}
-
-  postcss-js@4.0.1:
-    resolution: {integrity: sha512-dDLF8pEO191hJMtlHFPRa8xsizHaM82MLfNkUHdUtVEV3tgTp5oj+8qbEqYM57SLfc74KSbw//4SeJma2LRVIw==}
+  postcss-js@4.1.0:
+    resolution: {integrity: sha512-oIAOTqgIo7q2EOwbhb8UalYePMvYoIeRY2YKntdpFQXNosSu3vLrniGgmH9OKs/qAkfoj5oB3le/7mINW1LCfw==}
     engines: {node: ^12 || ^14 || >= 16}
     peerDependencies:
       postcss: ^8.4.21
 
+  postcss-js@5.0.3:
+    resolution: {integrity: sha512-yqxfMZ2NKo8MH0xcj6Yb1sos9Vk2aNzVi0i6k0nWH0LaLQQ1lke9DGWDMa80+tzHk+tLzfKa3pepOFcPSM6Yow==}
+    engines: {node: ^20 || ^22 || >= 24}
+    peerDependencies:
+      postcss: ^8.4.21
+
   postcss-load-config@4.0.2:
     resolution: {integrity: sha512-bSVhyJGL00wMVoPUzAVAnbEoWyqRxkjv64tUl427SKnPrENtq6hJwUojroMz2VB+Q1edmi4IfrAPpami5VVgMQ==}
     engines: {node: '>= 14'}
@@ -23674,14 +23676,13 @@ snapshots:
       read-cache: 1.0.0
       resolve: 1.22.8
 
-  postcss-js@3.0.3:
+  postcss-js@4.1.0(postcss@8.4.47):
     dependencies:
       camelcase-css: 2.0.1
       postcss: 8.4.47
 
-  postcss-js@4.0.1(postcss@8.4.47):
+  postcss-js@5.0.3(postcss@8.4.47):
     dependencies:
-      camelcase-css: 2.0.1
       postcss: 8.4.47
 
   postcss-load-config@4.0.2(postcss@8.4.47)(ts-node@10.9.2(@types/node@25.0.3)(typescript@5.9.3)):
@@ -25562,7 +25563,7 @@ snapshots:
       picocolors: 1.0.0
       postcss: 8.4.47
       postcss-import: 15.1.0(postcss@8.4.47)
-      postcss-js: 4.0.1(postcss@8.4.47)
+      postcss-js: 4.1.0(postcss@8.4.47)
       postcss-load-config: 4.0.2(postcss@8.4.47)(ts-node@10.9.2(@types/node@25.0.3)(typescript@5.9.3))
       postcss-nested: 6.2.0(postcss@8.4.47)
       postcss-selector-parser: 6.1.2