diff --git a/package.json b/package.json
index e462978..7f4be78 100644
--- a/package.json
+++ b/package.json
@@ -32,7 +32,7 @@
   },
   "devDependencies": {
     "@ember/optional-features": "^1.3.0",
-    "@fullhuman/postcss-purgecss": "^2.3.0",
+    "@fullhuman/postcss-purgecss": "^3.1.3",
     "@glimmer/component": "^1.0.0",
     "@glimmer/tracking": "^1.0.0",
     "babel-eslint": "^10.0.3",
diff --git a/yarn.lock b/yarn.lock
index 97e99ae..257b2f9 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -2114,7 +2114,7 @@
     resolve "^1.8.1"
     semver "^5.6.0"
 
-"@fullhuman/postcss-purgecss@^2.1.2", "@fullhuman/postcss-purgecss@^2.3.0":
+"@fullhuman/postcss-purgecss@^2.1.2":
   version "2.3.0"
   resolved "https://registry.yarnpkg.com/@fullhuman/postcss-purgecss/-/postcss-purgecss-2.3.0.tgz#50a954757ec78696615d3e118e3fee2d9291882e"
   integrity sha512-qnKm5dIOyPGJ70kPZ5jiz0I9foVOic0j+cOzNDoo8KoCf6HjicIZ99UfO2OmE7vCYSKAAepEwJtNzpiiZAh9xw==
@@ -2122,6 +2122,13 @@
     postcss "7.0.32"
     purgecss "^2.3.0"
 
+"@fullhuman/postcss-purgecss@^3.1.3":
+  version "3.1.3"
+  resolved "https://registry.yarnpkg.com/@fullhuman/postcss-purgecss/-/postcss-purgecss-3.1.3.tgz#47af7b87c9bfb3de4bc94a38f875b928fffdf339"
+  integrity sha512-kwOXw8fZ0Lt1QmeOOrd+o4Ibvp4UTEBFQbzvWldjlKv5n+G9sXfIPn1hh63IQIL8K8vbvv1oYMJiIUbuy9bGaA==
+  dependencies:
+    purgecss "^3.1.3"
+
 "@glimmer/compiler@^0.42.0":
   version "0.42.0"
   resolved "https://registry.yarnpkg.com/@glimmer/compiler/-/compiler-0.42.0.tgz#8c3852e27177bbecd3eed5bdbd15ec729e09ef8a"
@@ -5360,6 +5367,11 @@ color@^3.1.2:
     color-convert "^1.9.1"
     color-string "^1.5.2"
 
+colorette@^1.2.2:
+  version "1.2.2"
+  resolved "https://registry.yarnpkg.com/colorette/-/colorette-1.2.2.tgz#cbcc79d5e99caea2dbf10eb3a26fd8b3e6acfa94"
+  integrity sha512-MKGMzyfeuutC/ZJ1cba9NqcNpfeqMUcYmyF1ZFY6/Cn7CNSAKx6a+s48sqLqyAiZuaP2TcqMhoo+dlwFnVxT9w==
+
 colors@1.0.3:
   version "1.0.3"
   resolved "https://registry.yarnpkg.com/colors/-/colors-1.0.3.tgz#0433f44d809680fdeb60ed260f1b0c262e82a40b"
@@ -5417,6 +5429,11 @@ commander@^5.0.0:
   resolved "https://registry.yarnpkg.com/commander/-/commander-5.1.0.tgz#46abbd1652f8e059bddaef99bbdcb2ad9cf179ae"
   integrity sha512-P0CysNDQ7rtVw4QIQtm+MRxV66vKFSvlsQvGYXZWR3qFU0jlMKHZZZgw8e+8DSah4UDKMqnknRDQz+xuQXQ/Zg==
 
+commander@^6.0.0:
+  version "6.2.1"
+  resolved "https://registry.yarnpkg.com/commander/-/commander-6.2.1.tgz#0792eb682dfbc325999bb2b84fddddba110ac73c"
+  integrity sha512-U7VdrJFnJgo4xjrHpTzu0yrHPGImdsmD95ZlgYSEajAn2JKzDhDTPG9kBTefmObL2w/ngeZnilk+OV9CG3d7UA==
+
 common-tags@^1.4.0, common-tags@^1.8.0:
   version "1.8.0"
   resolved "https://registry.yarnpkg.com/common-tags/-/common-tags-1.8.0.tgz#8e3153e542d4a39e9b10554434afaaf98956a937"
@@ -11017,6 +11034,11 @@ nan@^2.9.2:
   version "2.10.0"
   resolved "https://registry.yarnpkg.com/nan/-/nan-2.10.0.tgz#96d0cd610ebd58d4b4de9cc0c6828cda99c7548f"
 
+nanoid@^3.1.23:
+  version "3.1.23"
+  resolved "https://registry.yarnpkg.com/nanoid/-/nanoid-3.1.23.tgz#f744086ce7c2bc47ee0a8472574d5c78e4183a81"
+  integrity sha512-FiB0kzdP0FFVGDKlRLEQ1BgDzU87dy5NnzjeW9YZNt+/c3+q82EQDUwniSAUxp/F0gFNI1ZhKU1FqYsMuqZVnw==
+
 nanomatch@^1.2.9:
   version "1.2.9"
   resolved "https://registry.yarnpkg.com/nanomatch/-/nanomatch-1.2.9.tgz#879f7150cb2dab7a471259066c104eee6e0fa7c2"
@@ -11892,6 +11914,15 @@ postcss@^6.0.1, postcss@^6.0.17, postcss@^6.0.9:
     source-map "^0.6.1"
     supports-color "^5.4.0"
 
+postcss@^8.2.1:
+  version "8.3.5"
+  resolved "https://registry.yarnpkg.com/postcss/-/postcss-8.3.5.tgz#982216b113412bc20a86289e91eb994952a5b709"
+  integrity sha512-NxTuJocUhYGsMiMFHDUkmjSKT3EdH4/WbGF6GCi1NDGk+vbcUTun4fpbOqaPtD8IIsztA2ilZm2DhYCuyN58gA==
+  dependencies:
+    colorette "^1.2.2"
+    nanoid "^3.1.23"
+    source-map-js "^0.6.2"
+
 prelude-ls@~1.1.2:
   version "1.1.2"
   resolved "https://registry.yarnpkg.com/prelude-ls/-/prelude-ls-1.1.2.tgz#21932a549f5e52ffd9a827f570e04be62a97da54"
@@ -12072,6 +12103,16 @@ purgecss@^2.3.0:
     postcss "7.0.32"
     postcss-selector-parser "^6.0.2"
 
+purgecss@^3.1.3:
+  version "3.1.3"
+  resolved "https://registry.yarnpkg.com/purgecss/-/purgecss-3.1.3.tgz#26987ec09d12eeadc318e22f6e5a9eb0be094f41"
+  integrity sha512-hRSLN9mguJ2lzlIQtW4qmPS2kh6oMnA9RxdIYK8sz18QYqd6ePp4GNDl18oWHA1f2v2NEQIh51CO8s/E3YGckQ==
+  dependencies:
+    commander "^6.0.0"
+    glob "^7.0.0"
+    postcss "^8.2.1"
+    postcss-selector-parser "^6.0.2"
+
 q@^1.1.2:
   version "1.5.1"
   resolved "https://registry.yarnpkg.com/q/-/q-1.5.1.tgz#7e32f75b41381291d04611f1bf14109ac00651d7"
@@ -13159,6 +13200,11 @@ source-list-map@^2.0.0:
   resolved "https://registry.yarnpkg.com/source-list-map/-/source-list-map-2.0.1.tgz#3993bd873bfc48479cca9ea3a547835c7c154b34"
   integrity sha512-qnQ7gVMxGNxsiL4lEuJwe/To8UnK7fAnmbGEEH8RpLouuKbeEm0lhbQVFIrNSuB+G7tVrAlVsZgETT5nljf+Iw==
 
+source-map-js@^0.6.2:
+  version "0.6.2"
+  resolved "https://registry.yarnpkg.com/source-map-js/-/source-map-js-0.6.2.tgz#0bb5de631b41cfbda6cfba8bd05a80efdfd2385e"
+  integrity sha512-/3GptzWzu0+0MBQFrDKzw/DvvMTUORvgY6k6jd/VS6iCR4RDTKWH6v6WPwQoUO8667uQEf9Oe38DxAYWY5F/Ug==
+
 source-map-resolve@^0.5.0:
   version "0.5.2"
   resolved "https://registry.yarnpkg.com/source-map-resolve/-/source-map-resolve-0.5.2.tgz#72e2cc34095543e43b2c62b2c4c10d4a9054f259"