code clean up

index.html

@@ -1,16 +1,13 @@
 <!DOCTYPE html>
-<html lang="en">
+<html lang="zh-cmn-Hans">
 <head>
-  <meta charset="UTF-8">
-  <title>Demo</title>
-  <link rel="stylesheet" href="index.css" />
+    <meta charset="UTF-8">
+    <title>Private Cloud Music</title>
+    <link rel="stylesheet" href="index.css" />
 </head>
 <body>
-
-<div id="root"></div>
-
-<script src="common.js"></script>
-<script src="index.js"></script>
-
+    <div id="root"></div>
+    <script src="common.js"></script>
+    <script src="index.js"></script>
 </body>
 </html>