修改绑定功能
diff --git a/www/bill.html b/www/bill.html
index e70285f..e2b99b1 100644
--- a/www/bill.html
+++ b/www/bill.html
@@ -16,7 +16,7 @@
 
 <body>
     <header class="aui-bar aui-bar-nav" style="padding-top:25px;">
-        <a class="aui-pull-left" href="javascript:window.history.back()">
+        <a class="aui-pull-left" href="javascript:window.history.go(-1)">
             <span class="aui-iconfont aui-icon-left"></span>
         </a>
         <div class="aui-title">账单</div>