diff --git a/package.json b/package.json
index a03518a..3cc212d 100644
--- a/package.json
+++ b/package.json
@@ -35,7 +35,7 @@
         "jsdom": "^16.6.0",
         "markdown-it": "^12.0.6",
         "markdown-it-anchor": "^7.1.0",
-        "postcss": "^8.3.2",
+        "postcss": "^8.4.18",
         "postcss-cli": "^8.3.1",
         "rollup": "^2.51.2",
         "rollup-plugin-postcss": "^4.0.0",
diff --git a/yarn.lock b/yarn.lock
index ce240aa..acb40ae 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -2016,7 +2016,7 @@ __metadata:
     markdown-it-anchor: ^7.1.0
     markdownlint: ^0.23.1
     markdownlint-cli2: ^0.1.3
-    postcss: ^8.3.2
+    postcss: ^8.4.18
     postcss-cli: ^8.3.1
     prettier: ^2.3.1
     rollup: ^2.51.2
@@ -5244,7 +5244,7 @@ __metadata:
   languageName: node
   linkType: hard
 
-"postcss@npm:^8.1.6, postcss@npm:^8.3.2, postcss@npm:^8.3.5":
+"postcss@npm:^8.1.6, postcss@npm:^8.3.5":
   version: 8.4.14
   resolution: "postcss@npm:8.4.14"
   dependencies:
@@ -5255,6 +5255,17 @@ __metadata:
   languageName: node
   linkType: hard
 
+"postcss@npm:^8.4.18":
+  version: 8.4.18
+  resolution: "postcss@npm:8.4.18"
+  dependencies:
+    nanoid: ^3.3.4
+    picocolors: ^1.0.0
+    source-map-js: ^1.0.2
+  checksum: 9349fd99849b2e3d2e134ff949b7770ecb12375f352723ce2bcc06167eba3850ea7844c1b191a85cd915d6a396b4e8ee9a5267e6cc5d8d003d0cbc7a97555d39
+  languageName: node
+  linkType: hard
+
 "posthtml-parser@npm:^0.11.0":
   version: 0.11.0
   resolution: "posthtml-parser@npm:0.11.0"