diff --git a/camel-case.js b/camel-case.js
index 23c21fd..f182de4 100644
--- a/camel-case.js
+++ b/camel-case.js
@@ -1,8 +1,11 @@
 "use strict";
 function camelCase (str) {
 	return str.replace(/[\w-]+/g, (s) => (
-		/^-?([a-z]+(?:-[a-z]+)+)$/.test(s)
-			? RegExp.$1.replace(
+		/^-?[a-z]+(?:-[a-z]+)+$/.test(s)
+			? s.replace(
+				/^-(ms|moz|khtml|epub|(\w+-?)*webkit)(?=-)/i,
+				"$1"
+			).replace(
 				/-\w/g,
 				s => (
 					s[1].toUpperCase()
diff --git a/package.json b/package.json
index a4a5a10..b42a459 100644
--- a/package.json
+++ b/package.json
@@ -38,8 +38,9 @@
     "check-coverage": true
   },
   "scripts": {
-    "test": "nyc mocha --no-timeouts",
-    "debug": "mocha  --inspect --debug-brk --no-timeouts"
+    "mocha": "mocha --no-timeouts",
+    "test": "nyc npm run mocha",
+    "debug": "npm run mocha -- --inspect-brk"
   },
   "dependencies": {
     "@babel/core": "^7.0.0"
@@ -52,12 +53,12 @@
     "postcss-syntax": ">=0.33.0"
   },
   "devDependencies": {
-    "autoprefixer": "^9.1.1",
+    "autoprefixer": "^9.1.5",
     "chai": "^4.1.2",
-    "codecov": "^3.0.4",
-    "json5": "^1.0.1",
+    "codecov": "^3.1.0",
+    "json5": "^2.0.1",
     "mocha": "^5.2.0",
-    "nyc": "^12.0.2",
+    "nyc": "^13.0.1",
     "postcss": "^7.0.2",
     "postcss-parser-tests": "^6.3.0",
     "postcss-safe-parser": "^4.0.1",
diff --git a/test/camel-case.js b/test/camel-case.js
index da2621c..d90e4a2 100644
--- a/test/camel-case.js
+++ b/test/camel-case.js
@@ -5,16 +5,19 @@ const camelCase = require("../camel-case");
 const unCamelCase = require("../un-camel-case");
 
 const data = {
+	borderTopLeftRadius: "border-top-left-radius",
+	backgroundImage: "background-image",
 	xwebkitAnimation: "-xwebkit-animation",
 	webkitAnimation: "-webkit-animation",
 	epubAnimation: "-epub-animation",
 	mozAnimation: "-moz-animation",
 	msAnimation: "-ms-animation",
-	oAnimation: "-o-animation",
-	xAnimation: "-x-animation",
+	OAnimation: "-o-animation",
+	XAnimation: "-x-animation",
 	webkitApp: "-webkit-app",
-	borderTopLeftRadius: "border-top-left-radius",
-	backgroundImage: "background-image",
+	onChange: "on-change",
+	OnChange: "-on-change",
+	zIndex: "z-index",
 	"::selection": "::selection",
 	"::mozSelection": "::-moz-selection",
 	"::mozSelection,::selection": "::-moz-selection,::selection",
@@ -50,12 +53,6 @@ describe("camelCase", () => {
 });
 
 describe("unCamelCase", () => {
-	it("onChange => on-change", () => {
-		expect(unCamelCase("onChange")).to.equal("on-change");
-	});
-	it("OnChange => -on-change", () => {
-		expect(unCamelCase("OnChange")).to.equal("-on-change");
-	});
 	testCases.forEach(testCase => {
 		it(`${testCase.camel} => ${testCase.unCamel}`, () => {
 			expect(unCamelCase(testCase.camel)).to.equal(testCase.unCamel);
diff --git a/test/non-style.js b/test/non-style.js
index 7b330b3..0b5e254 100644
--- a/test/non-style.js
+++ b/test/non-style.js
@@ -1,7 +1,7 @@
 "use strict";
 const spawnSync = require("child_process").spawnSync;
 const fs = require("fs");
-const files = spawnSync("git", ["ls-files"], {encoding: "utf8"}).stdout.match(/^.+$/gm).filter(file => file.endsWith(".js"));
+const files = spawnSync("git", ["ls-files"], { encoding: "utf8" }).stdout.match(/^.+$/gm).filter(file => file.endsWith(".js"));
 const syntax = require("../");
 const expect = require("chai").expect;
 
diff --git a/un-camel-case.js b/un-camel-case.js
index ba322c1..47b1a6e 100644
--- a/un-camel-case.js
+++ b/un-camel-case.js
@@ -1,13 +1,13 @@
 "use strict";
 function unCamelCase (str) {
 	return str.replace(/[\w-]+/g, (s) => (
-		/^[a-z]*(?:[A-Z][a-z]+)+$/.test(s)
+		/^[A-Z]?[a-z]*(?:[A-Z][a-z]+)+$/.test(s)
 			? s.replace(
 				/[A-Z]/g,
 				s => "-" + s.toLowerCase()
 			).replace(
-				/^(\w|ms|moz|khtml|epub|\w*webkit)-/,
-				"-$1-"
+				/^(o|ms|moz|khtml|epub|(\w+-?)*webkit)(?=-)/i,
+				"-$1"
 			)
 			: s
 	));