Update index.html

Author: 飞龙

index.html

@@ -40,10 +40,13 @@
       <iframe align="middle" src="https://ghbtns.com/github-btn.html?user=apachecn&repo=scikit-learn-doc-zh&type=fork&count=true" frameborder="0" scrolling="0" width="100px" height="25px"></iframe>
       <a target="_blank" href="//shang.qq.com/wpa/qunwpa?idkey=bcee938030cc9e1552deb3bd9617bbbf62d3ec1647e4b60d9cd6b6e8f78ddc03"><img border="0" src="//pub.idqqimg.com/wpa/images/group.png" alt="ML | ApacheCN" title="ML | ApacheCN"></a></p>
       <div style="text-align:center;margin:0 0 10.5px;">
+        <!-- google ads -->
         <ins class="adsbygoogle"
              style="display:inline-block;width:728px;height:90px"
              data-ad-client="ca-pub-3565452474788507"
              data-ad-slot="2543897000"></ins>
+        <!-- amazon ads -->
+        <iframe src="https://rcm-cn.amazon-adsystem.com/e/cm?o=28&p=48&l=ez&f=ifr&linkID=baf97d89d280aded8e8f18979d68cadf&t=flygonnet-23&tracking_id=flygonnet-23" width="728" height="90" scrolling="no" border="0" marginwidth="0" style="border:none;" frameborder="0"></iframe>
       </div>
     </div>
   </script>
@@ -70,4 +73,4 @@
 
   <script src="//unpkg.com/docsify/lib/docsify.min.js"></script>
 </body>
-</html>
+</html>