diff --git a/package.json b/package.json
index 3b23931..1dbdfac 100644
--- a/package.json
+++ b/package.json
@@ -24,7 +24,7 @@
   },
   "dependencies": {
     "cheerio": "1.0.0-rc.3",
-    "css-tree": "1.0.0-alpha.39",
+    "css-tree": "1.0.0",
     "csso": "4.0.3",
     "filesize": "^6.0.0",
     "minimist": "^1.2.0",
diff --git a/yarn.lock b/yarn.lock
index 5c28dd8..36c6dc2 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -1222,6 +1222,14 @@ css-select@~1.2.0:
     domutils "1.5.1"
     nth-check "~1.0.1"
 
+css-tree@1.0.0:
+  version "1.0.0"
+  resolved "https://registry.yarnpkg.com/css-tree/-/css-tree-1.0.0.tgz#21993fa270d742642a90409a2c0cb3ac0298adf6"
+  integrity sha512-CdVYz/Yuqw0VdKhXPBIgi8DO3NicJVYZNWeX9XcIuSp9ZoFT5IcleVRW07O5rMjdcx1mb+MEJPknTTEW7DdsYw==
+  dependencies:
+    mdn-data "2.0.12"
+    source-map "^0.6.1"
+
 css-tree@1.0.0-alpha.39:
   version "1.0.0-alpha.39"
   resolved "https://registry.yarnpkg.com/css-tree/-/css-tree-1.0.0-alpha.39.tgz#2bff3ffe1bb3f776cf7eefd91ee5cba77a149eeb"
@@ -2838,6 +2846,11 @@ map-visit@^1.0.0:
   dependencies:
     object-visit "^1.0.0"
 
+mdn-data@2.0.12:
+  version "2.0.12"
+  resolved "https://registry.yarnpkg.com/mdn-data/-/mdn-data-2.0.12.tgz#bbb658d08b38f574bbb88f7b83703defdcc46844"
+  integrity sha512-ULbAlgzVb8IqZ0Hsxm6hHSlQl3Jckst2YEQS7fODu9ilNWy2LvcoSY7TRFIktABP2mdppBioc66va90T+NUs8Q==
+
 mdn-data@2.0.6:
   version "2.0.6"
   resolved "https://registry.yarnpkg.com/mdn-data/-/mdn-data-2.0.6.tgz#852dc60fcaa5daa2e8cf6c9189c440ed3e042978"