feat!: implement css lexer & parser

Author: littledivy

debug.js

@@ -0,0 +1,11 @@
+function debug(label) {
+  return _debug.bind(null, label);
+}
+
+function _debug(label) {
+  var args = [].slice.call(arguments, 1);
+  args.unshift('[' + label + ']');
+  process.stderr.write(args.join(' ') + '\n');
+}
+
+export default debug;