diff --git a/demo-echarts.html b/demo-echarts.html
index 5b729a4..0d74d7f 100644
--- a/demo-echarts.html
+++ b/demo-echarts.html
@@ -2,15 +2,34 @@
 <html>
 <head>
     <meta charset="utf-8">
+    <style>
+        body{
+            text-align: center;
+        }
+        table {
+            margin: auto;
+            text-align: left;
+        }
+        footer{
+            padding: 2.5em;
+        }
+        #chart-container{
+            height: 520px;
+        }
+    </style>
 </head>
 <body>
     
     <h2>Map</h2>
-    <div id="chart-container" style="height: 500px"></div>
+    <div id="chart-container"></div>
 
     <h2>Table</h2>
     <div id="table-container"></div>
 
+    <footer>
+       <a href="https://github.com/Surbowl/world-geo-json-zh">GitHub - Surbowl/world-geo-json-zh</a>
+    </footer>
+
     <script type="text/javascript" src="https://cdn.jsdelivr.net/npm/echarts@5.2.2/dist/echarts.min.js"></script>
     <script type="module">
         // load word geo json zh data
@@ -80,4 +99,4 @@ <h2>Table</h2>
         }
     </script>
 </body>
-</html>
\ No newline at end of file
+</html>
