diff --git a/package.json b/package.json
index 25e85462..95031e40 100644
--- a/package.json
+++ b/package.json
@@ -74,7 +74,7 @@
     "less-loader": "^4.1.0",
     "mocha": "^3.2.0",
     "node-sass": "^4.5.3",
-    "postcss-loader": "^2.1.5",
+    "postcss-loader": "^3.0.0",
     "preact": "^8.2.1",
     "preact-compat": "^3.17.0",
     "sass-loader": "^7.0.1",
diff --git a/yarn.lock b/yarn.lock
index 34278d69..f072670c 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -1008,6 +1008,11 @@ adjust-sourcemap-loader@^1.1.0:
     object-path "^0.9.2"
     regex-parser "^2.2.9"
 
+ajv-errors@^1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/ajv-errors/-/ajv-errors-1.0.0.tgz#ecf021fa108fd17dfb5e6b383f2dd233e31ffc59"
+  integrity sha1-7PAh+hCP0X37Xms4Py3SM+Mf/Fk=
+
 ajv-keywords@^2.1.0:
   version "2.1.1"
   resolved "https://registry.yarnpkg.com/ajv-keywords/-/ajv-keywords-2.1.1.tgz#617997fc5f60576894c435f940d819e135b80762"
@@ -6257,15 +6262,15 @@ postcss-load-config@^2.0.0:
     cosmiconfig "^4.0.0"
     import-cwd "^2.0.0"
 
-postcss-loader@^2.1.5:
-  version "2.1.6"
-  resolved "https://registry.yarnpkg.com/postcss-loader/-/postcss-loader-2.1.6.tgz#1d7dd7b17c6ba234b9bed5af13e0bea40a42d740"
-  integrity sha512-hgiWSc13xVQAq25cVw80CH0l49ZKlAnU1hKPOdRrNj89bokRr/bZF2nT+hebPPF9c9xs8c3gw3Fr2nxtmXYnNg==
+postcss-loader@^3.0.0:
+  version "3.0.0"
+  resolved "https://registry.yarnpkg.com/postcss-loader/-/postcss-loader-3.0.0.tgz#6b97943e47c72d845fa9e03f273773d4e8dd6c2d"
+  integrity sha512-cLWoDEY5OwHcAjDnkyRQzAXfs2jrKjXpO/HQFcc5b5u/r7aa471wdmChmwfnv7x2u840iat/wi0lQ5nbRgSkUA==
   dependencies:
     loader-utils "^1.1.0"
-    postcss "^6.0.0"
+    postcss "^7.0.0"
     postcss-load-config "^2.0.0"
-    schema-utils "^0.4.0"
+    schema-utils "^1.0.0"
 
 postcss-merge-idents@^2.1.5:
   version "2.1.7"
@@ -6477,7 +6482,7 @@ postcss@^5.0.10, postcss@^5.0.11, postcss@^5.0.12, postcss@^5.0.13, postcss@^5.0
     source-map "^0.5.6"
     supports-color "^3.2.3"
 
-postcss@^6.0.0, postcss@^6.0.1, postcss@^6.0.20, postcss@^6.0.23:
+postcss@^6.0.1, postcss@^6.0.20, postcss@^6.0.23:
   version "6.0.23"
   resolved "https://registry.yarnpkg.com/postcss/-/postcss-6.0.23.tgz#61c82cc328ac60e677645f979054eb98bc0e3324"
   integrity sha512-soOk1h6J3VMTZtVeVpv15/Hpdl2cBLX3CAw4TAbkpTJiNPk9YP/zWcD1ND+xEtvyuuvKzbxliTOIyvkSeSJ6ag==
@@ -6486,6 +6491,15 @@ postcss@^6.0.0, postcss@^6.0.1, postcss@^6.0.20, postcss@^6.0.23:
     source-map "^0.6.1"
     supports-color "^5.4.0"
 
+postcss@^7.0.0:
+  version "7.0.5"
+  resolved "https://registry.yarnpkg.com/postcss/-/postcss-7.0.5.tgz#70e6443e36a6d520b0fd4e7593fcca3635ee9f55"
+  integrity sha512-HBNpviAUFCKvEh7NZhw1e8MBPivRszIiUnhrJ+sBFVSYSqubrzwX3KG51mYgcRHX8j/cAgZJedONZcm5jTBdgQ==
+  dependencies:
+    chalk "^2.4.1"
+    source-map "^0.6.1"
+    supports-color "^5.5.0"
+
 preact-compat@^3.17.0:
   version "3.18.0"
   resolved "https://registry.yarnpkg.com/preact-compat/-/preact-compat-3.18.0.tgz#ca430cc1f67193fb9feaf7c510832957b2ebe701"
@@ -7242,7 +7256,7 @@ sax@^1.1.4, sax@^1.2.4, sax@~1.2.1:
   resolved "https://registry.yarnpkg.com/sax/-/sax-1.2.4.tgz#2816234e2378bddc4e5354fab5caa895df7100d9"
   integrity sha512-NqVDv9TpANUjFm0N8uM5GxL36UgKi9/atZw+x7YFnQ8ckwFGKrl4xX4yWtrey3UJm5nP1kUbnYgLopqWNSRhWw==
 
-schema-utils@^0.4.0, schema-utils@^0.4.3, schema-utils@^0.4.4, schema-utils@^0.4.5:
+schema-utils@^0.4.3, schema-utils@^0.4.4, schema-utils@^0.4.5:
   version "0.4.5"
   resolved "https://registry.yarnpkg.com/schema-utils/-/schema-utils-0.4.5.tgz#21836f0608aac17b78f9e3e24daff14a5ca13a3e"
   integrity sha512-yYrjb9TX2k/J1Y5UNy3KYdZq10xhYcF8nMpAW6o3hy6Q8WSIEf9lJHG/ePnOBfziPM3fvQwfOwa13U/Fh8qTfA==
@@ -7250,6 +7264,15 @@ schema-utils@^0.4.0, schema-utils@^0.4.3, schema-utils@^0.4.4, schema-utils@^0.4
     ajv "^6.1.0"
     ajv-keywords "^3.1.0"
 
+schema-utils@^1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/schema-utils/-/schema-utils-1.0.0.tgz#0b79a93204d7b600d4b2850d1f66c2a34951c770"
+  integrity sha512-i27Mic4KovM/lnGsy8whRCHhc7VicJajAjTrYg11K9zfZXnYIt4k5F+kZkwjnrhKzLic/HLU4j11mjsz2G/75g==
+  dependencies:
+    ajv "^6.1.0"
+    ajv-errors "^1.0.0"
+    ajv-keywords "^3.1.0"
+
 scss-tokenizer@^0.2.3:
   version "0.2.3"
   resolved "https://registry.yarnpkg.com/scss-tokenizer/-/scss-tokenizer-0.2.3.tgz#8eb06db9a9723333824d3f5530641149847ce5d1"
@@ -7836,7 +7859,7 @@ supports-color@^5.1.0, supports-color@^5.4.0:
   dependencies:
     has-flag "^3.0.0"
 
-supports-color@^5.3.0:
+supports-color@^5.3.0, supports-color@^5.5.0:
   version "5.5.0"
   resolved "https://registry.yarnpkg.com/supports-color/-/supports-color-5.5.0.tgz#e2e69a44ac8772f78a1ec0b35b689df6530efc8f"
   integrity sha512-QjVjwdXIt408MIiAqCX4oUKsgU2EqAGzs2Ppkm4aQYbjm+ZEWEcW4SfFNTr4uMNZma0ey4f5lgLrkB0aX0QMow==