add initial marp implementation with sample content and build configuration

node_modules/@marp-team/marpit/lib/postcss/pagination.js

@@ -0,0 +1,30 @@
+"use strict";
+
+Object.defineProperty(exports, "__esModule", {
+  value: true
+});
+exports.pagination = exports.default = void 0;
+var _postcss_plugin = _interopRequireDefault(require("../helpers/postcss_plugin"));
+function _interopRequireDefault(e) { return e && e.__esModule ? e : { default: e }; }
+/** @module */
+
+/**
+ * Marpit PostCSS pagination plugin.
+ *
+ * Marpit uses `section::after` to show the pagination on each slide. It defines
+ * in the scaffold theme.
+ *
+ * This plugin will comment out a `content` declaration defined in any
+ * `section::after` of the root, to prevent override the defined attribute for
+ * paginating.
+ *
+ * @function pagination
+ */
+const pagination = exports.pagination = (0, _postcss_plugin.default)('marpit-postcss-pagination', () => css => {
+  css.walkRules(rule => {
+    if (rule.selectors.some(selector => /^section(?![\w-])[^\s>+~]*::?after$/.test(selector.replace(/\[.*?\]/g, '')))) rule.walkDecls('content', decl => {
+      if (!decl.value.includes('attr(data-marpit-pagination)')) decl.replaceWith(`${decl.raw('before')}/* ${decl.toString()}; */`);
+    });
+  });
+});
+var _default = exports.default = pagination;