docs: add ga another way

Author: Simpleyyt

docs/index.html

@@ -17,7 +17,6 @@
     window.$docsify = {
       name: '🤖 AI Manus',
       repo: 'https://github.com/simpleyyt/ai-manus',
-      ga: 'G-9GBMY0CD5J',
       loadSidebar: true,
       subMaxLevel: 2,
       auto2top: true,
@@ -37,18 +36,26 @@
       },
     }
   </script>
-    <script type="module">
-      import mermaid from "https://cdn.jsdelivr.net/npm/mermaid@10/dist/mermaid.esm.min.mjs";
-      mermaid.initialize({ startOnLoad: true });
-      window.mermaid = mermaid;
-    </script>
-    <script src="//unpkg.com/docsify-mermaid@2.0.1/dist/docsify-mermaid.js"></script>
+  <script type="module">
+    import mermaid from "https://cdn.jsdelivr.net/npm/mermaid@10/dist/mermaid.esm.min.mjs";
+    mermaid.initialize({ startOnLoad: true });
+    window.mermaid = mermaid;
+  </script>
+  <!-- Google tag (gtag.js) -->
+  <script async src="https://www.googletagmanager.com/gtag/js?id=G-9GBMY0CD5J"></script>
+  <script>
+    window.dataLayer = window.dataLayer || [];
+    function gtag(){dataLayer.push(arguments);}
+    gtag('js', new Date());
+
+    gtag('config', 'G-9GBMY0CD5J');
+  </script>
+  <script src="//unpkg.com/docsify-mermaid@2.0.1/dist/docsify-mermaid.js"></script>
   <!-- Docsify v4 -->
   <script src="//cdn.jsdelivr.net/npm/docsify@4"></script>
   <script src="//cdn.jsdelivr.net/npm/docsify-copy-code/dist/docsify-copy-code.min.js"></script>
   <script src="//cdn.jsdelivr.net/npm/docsify/lib/plugins/emoji.min.js"></script>
   <script src="//unpkg.com/docsify-pagination/dist/docsify-pagination.min.js"></script>
-  <script src="//cdn.jsdelivr.net/npm/docsify/lib/plugins/ga.min.js"></script>
 </body>
 
 </html>