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+/**
+@license
+Copyright (c) 2016 The Polymer Project Authors. All rights reserved.
+This code may only be used under the BSD style license found at http://polymer.github.io/LICENSE.txt
+The complete set of authors may be found at http://polymer.github.io/AUTHORS.txt
+The complete set of contributors may be found at http://polymer.github.io/CONTRIBUTORS.txt
+Code distributed by Google as part of the polymer project is also
+subject to an additional IP rights grant found at http://polymer.github.io/PATENTS.txt
+*/
+
+/*
+Example library for adding document-level styles to ShadyCSS
+
+After DOMContentLoaded, synchronously add all document document level styles.
+Then, start a MutationObserver for dynamically added styles.
+
+Caveat: ShadyCSS will add a `scope` attribute to styles it controls, so do not add those styles.
+*/
+(function() {
+  'use strict';
+
+  const CustomStyleInterface = window.ShadyCSS.CustomStyleInterface;
+
+  function shouldAddDocumentStyle(n) {
+    return n.nodeType === Node.ELEMENT_NODE && n.localName === 'style' && !n.hasAttribute('scope');
+  }
+
+  function handler(mxns) {
+    for (let i = 0; i < mxns.length; i++) {
+      let mxn = mxns[i];
+      for (let j = 0; j < mxn.addedNodes.length; j++) {
+        let n = mxn.addedNodes[j];
+        if (shouldAddDocumentStyle(n)) {
+          CustomStyleInterface.addCustomStyle(n);
+        }
+      }
+    }
+  }
+
+  const observer = new MutationObserver(handler);
+
+  document.addEventListener('DOMContentLoaded', () => {
+    const candidates = document.querySelectorAll('custom-style');
+    for (let i = 0; i < candidates.length; i++) {
+      const candidate = candidates[i];
+      if (shouldAddDocumentStyle(candidate)) {
+        CustomStyleInterface.addCustomStyle(candidate);
+      }
+    }
+    observer.observe(document, {childList: true, subtree: true});
+  });
+
+  window.documentStyleFlush = () => {handler(observer.takeRecords())};
+})();
+\ No newline at end of file