diff --git a/package-lock.json b/package-lock.json
index f5533b4..423dafd 100644
--- a/package-lock.json
+++ b/package-lock.json
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       "integrity": "sha1-hFK0u36Dx8GI2AQcGoN8dz1ti7k=",
+      "dev": true,
+      "optional": true
+    },
+    "yaml": {
+      "version": "1.10.2",
+      "resolved": "https://registry.npmjs.org/yaml/-/yaml-1.10.2.tgz",
+      "integrity": "sha512-r3vXyErRCYJ7wg28yvBY5VSoAF8ZvlcW9/BwUzEtUsjvX/DKs24dIkuwjtuprwJJHsbyUbLApepYTR1BN4uHrg==",
       "dev": true
     },
     "yargs": {
diff --git a/package.json b/package.json
index 63cb824..e76b4f4 100644
--- a/package.json
+++ b/package.json
@@ -29,7 +29,7 @@
     "gulp-include": "^2.3.1",
     "gulp-jsmin": "^0.1.5",
     "gulp-less": "^4.0.1",
-    "gulp-postcss": "^7.0.1",
+    "gulp-postcss": "^9.0.1",
     "gulp-pug": "^4.0.1",
     "imagemin-pngquant": "^6.0.0"
   },