docs：更新文档

node_modules/postcss-selector-parser/dist/selectors/nesting.js

@@ -0,0 +1,32 @@
+"use strict";
+
+exports.__esModule = true;
+exports.default = void 0;
+
+var _node = _interopRequireDefault(require("./node"));
+
+var _types = require("./types");
+
+function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
+
+function _inheritsLoose(subClass, superClass) { subClass.prototype = Object.create(superClass.prototype); subClass.prototype.constructor = subClass; subClass.__proto__ = superClass; }
+
+var Nesting =
+/*#__PURE__*/
+function (_Node) {
+  _inheritsLoose(Nesting, _Node);
+
+  function Nesting(opts) {
+    var _this;
+
+    _this = _Node.call(this, opts) || this;
+    _this.type = _types.NESTING;
+    _this.value = '&';
+    return _this;
+  }
+
+  return Nesting;
+}(_node.default);
+
+exports.default = Nesting;
+module.exports = exports.default;