diff --git a/index.html b/index.html
index b752ca1..f19f923 100644
--- a/index.html
+++ b/index.html
@@ -8,6 +8,7 @@
   <script src="//code.jquery.com/ui/1.10.4/jquery-ui.min.js"></script>
 
   <script src="js/marked.js"></script>
+  <script src="js/store.js"></script>
   <script src="js/ditto.js"></script>
   <script src="js/prism.js"></script>
   <link rel="stylesheet" href="app/bower_components/normalize-css/normalize.css">
@@ -34,7 +35,7 @@
       ditto.sidebar_file = "sidebar.md",
 	  ditto.document_title = "ECMAScript 6入门",
       // where the docs are actually stored on github - so you can edit
-      ditto.base_url = "https://github.com/ruanyf/es6tutorial/edit/gh-pages/";  // <------- EDIT ME!!
+      ditto.base_url = "https://github.com/ruanyf/es6tutorial/edit/gh-pages";  // <------- EDIT ME!!
 
       // run
       ditto.run();
diff --git a/js/ditto.js b/js/ditto.js
index 6f90b6b..cd82774 100644
--- a/js/ditto.js
+++ b/js/ditto.js
@@ -11,6 +11,7 @@ var ditto = {
     sidebar: true,
     edit_button: true,
     back_to_top_button: true,
+    save_progress: true, // 保存阅读进度
 
     // initialize function
     run: initialize
@@ -195,6 +196,11 @@ function router() {
 
     var path = location.hash.replace("#", "./");
 
+    if (ditto.save_progress && store.get('menu-progress') !== location.hash) {
+        store.set('menu-progress', location.hash);
+        store.set('page-progress', 0);
+    }
+
     // default page if hash is empty
     if (location.pathname === "/index.html") {
         path = location.pathname.replace("index.html", ditto.index);
@@ -240,12 +246,6 @@ function router() {
 			})();
 		})();
 
-		if(location.hash !== ''){
-			$('html, body').animate({
-				scrollTop: $('#content').offset().top
-			}, 200);
-		}
-
 		if(location.hash==='' || location.hash===menu[0]){
 			$('#pageup').css('display','none');
 		}else{
@@ -264,16 +264,22 @@ function router() {
 			var wh = $w.height();
 			var h = $('body').height();
 			var sHeight = h - wh;
-			$w.off('scroll');
-			$w.on('scroll', function(){
+ 			var perc = ditto.save_progress ? store.get('page-progress') || 0 : 0;
+
+			$w.off('scroll').on('scroll', function(){
 				var perc = Math.max(0, Math.min(1, $w.scrollTop()/sHeight));
 				updateProgress(perc);
 			});
 
 			function updateProgress(perc){
 				$prog2.css({width : perc*100 + '%'});
+				ditto.save_progress && store.set('page-progress', perc);
 			}
 
+			updateProgress(perc);
+			$('html, body').animate({
+				scrollTop: sHeight * perc
+ 			}, 200);
 		}());
 
     }).fail(function() {
diff --git a/js/store.js b/js/store.js
new file mode 100644
index 0000000..915283b
--- /dev/null
+++ b/js/store.js
@@ -0,0 +1,2 @@
+/* Copyright (c) 2010-2013 Marcus Westin */
+this.JSON||(this.JSON={}),function(){function f(e){return e<10?"0"+e:e}function quote(e){return escapable.lastIndex=0,escapable.test(e)?'"'+e.replace(escapable,function(e){var t=meta[e];return typeof t=="string"?t:"\\u"+("0000"+e.charCodeAt(0).toString(16)).slice(-4)})+'"':'"'+e+'"'}function str(e,t){var n,r,i,s,o=gap,u,a=t[e];a&&typeof a=="object"&&typeof a.toJSON=="function"&&(a=a.toJSON(e)),typeof rep=="function"&&(a=rep.call(t,e,a));switch(typeof a){case"string":return quote(a);case"number":return isFinite(a)?String(a):"null";case"boolean":case"null":return String(a);case"object":if(!a)return"null";gap+=indent,u=[];if(Object.prototype.toString.apply(a)==="[object Array]"){s=a.length;for(n=0;n<s;n+=1)u[n]=str(n,a)||"null";return i=u.length===0?"[]":gap?"[\n"+gap+u.join(",\n"+gap)+"\n"+o+"]":"["+u.join(",")+"]",gap=o,i}if(rep&&typeof rep=="object"){s=rep.length;for(n=0;n<s;n+=1)r=rep[n],typeof r=="string"&&(i=str(r,a),i&&u.push(quote(r)+(gap?": ":":")+i))}else for(r in a)Object.hasOwnProperty.call(a,r)&&(i=str(r,a),i&&u.push(quote(r)+(gap?": ":":")+i));return i=u.length===0?"{}":gap?"{\n"+gap+u.join(",\n"+gap)+"\n"+o+"}":"{"+u.join(",")+"}",gap=o,i}}typeof Date.prototype.toJSON!="function"&&(Date.prototype.toJSON=function(e){return isFinite(this.valueOf())?this.getUTCFullYear()+"-"+f(this.getUTCMonth()+1)+"-"+f(this.getUTCDate())+"T"+f(this.getUTCHours())+":"+f(this.getUTCMinutes())+":"+f(this.getUTCSeconds())+"Z":null},String.prototype.toJSON=Number.prototype.toJSON=Boolean.prototype.toJSON=function(e){return this.valueOf()});var cx=/[\u0000\u00ad\u0600-\u0604\u070f\u17b4\u17b5\u200c-\u200f\u2028-\u202f\u2060-\u206f\ufeff\ufff0-\uffff]/g,escapable=/[\\\"\x00-\x1f\x7f-\x9f\u00ad\u0600-\u0604\u070f\u17b4\u17b5\u200c-\u200f\u2028-\u202f\u2060-\u206f\ufeff\ufff0-\uffff]/g,gap,indent,meta={"\b":"\\b","	":"\\t","\n":"\\n","\f":"\\f","\r":"\\r",'"':'\\"',"\\":"\\\\"},rep;typeof JSON.stringify!="function"&&(JSON.stringify=function(e,t,n){var r;gap="",indent="";if(typeof n=="number")for(r=0;r<n;r+=1)indent+=" ";else typeof n=="string"&&(indent=n);rep=t;if(!t||typeof t=="function"||typeof t=="object"&&typeof t.length=="number")return str("",{"":e});throw new Error("JSON.stringify")}),typeof JSON.parse!="function"&&(JSON.parse=function(text,reviver){function walk(e,t){var n,r,i=e[t];if(i&&typeof i=="object")for(n in i)Object.hasOwnProperty.call(i,n)&&(r=walk(i,n),r!==undefined?i[n]=r:delete i[n]);return reviver.call(e,t,i)}var j;text=String(text),cx.lastIndex=0,cx.test(text)&&(text=text.replace(cx,function(e){return"\\u"+("0000"+e.charCodeAt(0).toString(16)).slice(-4)}));if(/^[\],:{}\s]*$/.test(text.replace(/\\(?:["\\\/bfnrt]|u[0-9a-fA-F]{4})/g,"@").replace(/"[^"\\\n\r]*"|true|false|null|-?\d+(?:\.\d*)?(?:[eE][+\-]?\d+)?/g,"]").replace(/(?:^|:|,)(?:\s*\[)+/g,"")))return j=eval("("+text+")"),typeof reviver=="function"?walk({"":j},""):j;throw new SyntaxError("JSON.parse")})}(),function(e){function o(){try{return r in e&&e[r]}catch(t){return!1}}var t={},n=e.document,r="localStorage",i="script",s;t.disabled=!1,t.set=function(e,t){},t.get=function(e){},t.remove=function(e){},t.clear=function(){},t.transact=function(e,n,r){var i=t.get(e);r==null&&(r=n,n=null),typeof i=="undefined"&&(i=n||{}),r(i),t.set(e,i)},t.getAll=function(){},t.forEach=function(){},t.serialize=function(e){return JSON.stringify(e)},t.deserialize=function(e){if(typeof e!="string")return undefined;try{return JSON.parse(e)}catch(t){return e||undefined}};if(o())s=e[r],t.set=function(e,n){return n===undefined?t.remove(e):(s.setItem(e,t.serialize(n)),n)},t.get=function(e){return t.deserialize(s.getItem(e))},t.remove=function(e){s.removeItem(e)},t.clear=function(){s.clear()},t.getAll=function(){var e={};return t.forEach(function(t,n){e[t]=n}),e},t.forEach=function(e){for(var n=0;n<s.length;n++){var r=s.key(n);e(r,t.get(r))}};else if(n.documentElement.addBehavior){var u,a;try{a=new 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\ No newline at end of file