diff --git a/package-lock.json b/package-lock.json
index 8566f69..33b58d9 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -13,7 +13,7 @@
         "@ampproject/toolbox-optimizer": "2.9.0",
         "@ampproject/toolbox-runtime-fetch": "2.9.0",
         "amphtml-validator": "1.0.35",
-        "clean-css": "5.3.0",
+        "clean-css": "5.3.3",
         "eleventy": "^1.0.6",
         "probe-image-size": "7.2.3"
       },
@@ -2396,9 +2396,9 @@
       "dev": true
     },
     "node_modules/clean-css": {
-      "version": "5.3.0",
-      "resolved": "https://registry.npmjs.org/clean-css/-/clean-css-5.3.0.tgz",
-      "integrity": "sha512-YYuuxv4H/iNb1Z/5IbMRoxgrzjWGhOEFfd+groZ5dMCVkpENiMZmwspdrzBo9286JjM1gZJPAyL7ZIdzuvu2AQ==",
+      "version": "5.3.3",
+      "resolved": "https://registry.npmjs.org/clean-css/-/clean-css-5.3.3.tgz",
+      "integrity": "sha512-D5J+kHaVb/wKSFcyyV75uCn8fiY4sV38XJoe4CUyGQ+mOU/fMVYUdH1hJC+CJQ5uY3EnW27SbJYS4X8BiLrAFg==",
       "dependencies": {
         "source-map": "~0.6.0"
       },
@@ -10336,9 +10336,9 @@
       "dev": true
     },
     "clean-css": {
-      "version": "5.3.0",
-      "resolved": "https://registry.npmjs.org/clean-css/-/clean-css-5.3.0.tgz",
-      "integrity": "sha512-YYuuxv4H/iNb1Z/5IbMRoxgrzjWGhOEFfd+groZ5dMCVkpENiMZmwspdrzBo9286JjM1gZJPAyL7ZIdzuvu2AQ==",
+      "version": "5.3.3",
+      "resolved": "https://registry.npmjs.org/clean-css/-/clean-css-5.3.3.tgz",
+      "integrity": "sha512-D5J+kHaVb/wKSFcyyV75uCn8fiY4sV38XJoe4CUyGQ+mOU/fMVYUdH1hJC+CJQ5uY3EnW27SbJYS4X8BiLrAFg==",
       "requires": {
         "source-map": "~0.6.0"
       }
diff --git a/package.json b/package.json
index 9775a03..b8a780c 100644
--- a/package.json
+++ b/package.json
@@ -57,7 +57,7 @@
     "@ampproject/toolbox-optimizer": "2.9.0",
     "@ampproject/toolbox-runtime-fetch": "2.9.0",
     "amphtml-validator": "1.0.35",
-    "clean-css": "5.3.0",
+    "clean-css": "5.3.3",
     "eleventy": "^1.0.6",
     "probe-image-size": "7.2.3"
   },