增加替换按钮

index.html

@@ -4,7 +4,7 @@
     <meta charset="UTF-8" />
     <link rel="shortcut icon" href="/favicon.ico" />
     <meta name="viewport" content="width=device-width, initial-scale=1.0" />
-    <title>前端开发预览网站</title>
+    <title>前端开发学习平台</title>
     <link rel="stylesheet" href="/style.css" />
     <script>
       window.localStorage.setItem("maxkbMaskTip", true)