diff --git a/app/templates/userpage_get.html b/app/templates/userpage_get.html
index 68997ef..0488aea 100644
--- a/app/templates/userpage_get.html
+++ b/app/templates/userpage_get.html
@@ -5,6 +5,8 @@
     <meta name="viewport"
           content="width=device-width, initial-scale=1.0, minimum-scale=0.5, maximum-scale=3.0, user-scalable=yes"/>
     <meta name="format-detection" content="telephone=no"/>
+    <link href="https://cdn.jsdelivr.net/npm/bootstrap@5.3.1/dist/css/bootstrap.min.css" rel="stylesheet">
+    <script src="https://cdn.jsdelivr.net/npm/bootstrap@5.3.1/dist/js/bootstrap.bundle.min.js"></script>
 
     {{ yml['header'] | safe }}
     {% if yml['css']['item'] %}
@@ -26,12 +28,40 @@
         }
 
         @keyframes shakes {
-            10%, 90% { transform: translate3d(-1px, 0, 0); }
-            20%, 50% { transform: translate3d(+2px, 0, 0); }
-            30%, 70% { transform: translate3d(-4px, 0, 0); }
-            40%, 60% { transform: translate3d(+4px, 0, 0); }
-            50% { transform: translate3d(-4px, 0, 0); }
+            10%, 90% {
+                transform: translate3d(-1px, 0, 0);
+            }
+            20%, 50% {
+                transform: translate3d(+2px, 0, 0);
+            }
+            30%, 70% {
+                transform: translate3d(-4px, 0, 0);
+            }
+            40%, 60% {
+                transform: translate3d(+4px, 0, 0);
+            }
+            50% {
+                transform: translate3d(-4px, 0, 0);
+            }
         }
+
+        .lead {
+            font-size: 22px;
+            font-family: Helvetica, sans-serif;
+            white-space: pre-wrap;
+        }
+
+        .arrow {
+            padding: 0;
+            font-size: 20px;
+            line-height: 21px;
+            display: inline-block;
+        }
+
+        .arrow:hover {
+            cursor: pointer;
+        }
+
     </style>
 </head>
 <body>
@@ -39,53 +69,70 @@
     <p><b>English Pal for <font id="username" color="red">{{ username }}</font></b>
 
         {% if username ==  admin_name %}
-        <a class="btn btn-secondary" href="/admin" role="button" onclick="stopRead()">管理</a>
+            <a class="btn btn-secondary" href="/admin" role="button" onclick="stopRead()">管理</a>
         {% endif %}
         <a id="quit" class="btn btn-secondary" href="/logout" role="button" onclick="stopRead()">退出</a>
         <a class="btn btn-secondary" href="/reset" role="button" onclick="stopRead()">重设密码</a>
 
     </p>
-{#    {% for message in flashed_messages %}#} {# 根据user_service.userpage,取消了参数flashed_messages，因此注释了这段代码 #}
-{#        <div class="alert alert-warning" role="alert">Congratulations! {{ message }}</div>#}
-{#    {% endfor %}#}
+    {% for message in get_flashed_messages() %}
+        <div class="alert alert-warning alert-dismissible fade show" role="alert">
+            {{ message }}
+            <button type="button" class="btn-close" data-bs-dismiss="alert" aria-label="Close"></button>
+        </div>
+    {% endfor %}
 
-        <button class="btn btn-success" id="load_next_article" onclick="load_next_article()"> 下一篇 Next Article </button>
-        <button class="btn btn-success" id="load_pre_article" onclick="load_pre_article()" > 上一篇 Previous Article </button>
+    <button class="arrow" id="load_next_article" onclick="load_next_article();Reader.stopRead()"
+            title="下一篇 Next Article">⇨
+    </button>
+    <button class="arrow" id="load_pre_article" onclick="load_pre_article();Reader.stopRead()" style="display: none"
+            title="上一篇 Previous Article">⇦
+    </button>
 
     <p><b>阅读文章并回答问题</b></p>
     <div id="text-content">
         <div id="found">
-            <div class="alert alert-success" role="alert">According to your word list, your level is <span class="badge bg-success" id="user-level">{{ today_article["user_level"] }}</span>  and we have chosen an article with a difficulty level of <span class="badge bg-success" id="text_level">{{ today_article["text_level"] }}</span> for you.</div>
-                <p class="text-muted" id="date">Article added on: {{ today_article["date"] }}</p><br/>
-            <div class="p-3 mb-2 bg-light text-dark"><br/>
-            <p class="display-5" id="article_title">{{ today_article["article_title"] }}</p><br/>
-            <p class="lead"><font id="article" size=2>{{ today_article["article_body"] }}</font></p><br/>
-            <p><small class="text-muted" id="source">{{ today_article['source'] }}</small></p><br/>
-            <p><b id="question">{{ today_article['question'] }}</b></p><br/>
+            <div class="alert alert-success" role="alert">According to your word list, your level is <span
+                    class="text-decoration-underline" id="user_level">{{ today_article["user_level"] }}</span> and we
+                have chosen an article with a difficulty level of <span class="text-decoration-underline"
+                                                                        id="text_level">{{ today_article["text_level"] }}</span>
+                for you.
+            </div>
+            <p class="text-muted" id="date">Article added on: {{ today_article["date"] }}</p><br/>
+            <div class="p-3 mb-2 bg-light text-dark" style="margin: 0 0.5%;"><br/>
+                <p class="display-6" id="article_title">{{ today_article["article_title"] }}</p><br/>
+                <p class="lead"><font id="article">{{ today_article["article_body"] }}</font></p><br/>
+                <div>
+                    <p><small class="text-muted" id="source">{{ today_article['source'] }}</small></p><br/>
+                </div>
+
+                <p><b id="question">{{ today_article['question'] }}</b></p><br/>
                 <script type="text/javascript">
                     function toggle_visibility(id) { {# https://css-tricks.com/snippets/javascript/showhide-element/#}
                         const e = document.getElementById(id);
-                        if(e.style.display === 'block')
+                        if (e.style.display === 'block')
                             e.style.display = 'none';
                         else
                             e.style.display = 'block';
                     }
                 </script>
                 <button onclick="toggle_visibility('answer');">ANSWER</button>
-                <div id="answer" style="display:none;">{{ today_article['answer'] }}</div><br/>
+                <div id="answer" style="display:none;">{{ today_article['answer'] }}</div>
+                <br/>
             </div>
         </div>
         <div class="alert alert-success" role="alert" id="not_found" style="display:none;">
-            <p class="text-muted"><span class="badge bg-success">Notes:</span><br>No article is currently available for you. You can try again a few times or mark new words in the passage to improve your level.</p>
+            <p class="text-muted"><span class="badge bg-success">Notes:</span><br>No article is currently available for
+                you. You can try again a few times or mark new words in the passage to improve your level.</p>
         </div>
         <div class="alert alert-success" role="alert" id="read_all" style="display:none;">
             <p class="text-muted"><span class="badge bg-success">Notes:</span><br>You've read all the articles.</p>
         </div>
     </div>
 
-    <input type="checkbox" onclick="toggleHighlighting()" checked/>生词高亮
-    <input type="checkbox" onclick="onReadClick()" checked/>大声朗读
-    <input type="checkbox" onclick="onChooseClick()" checked/>划词入库
+    <input type="checkbox" id="highlightCheckbox" onclick="toggleHighlighting()"/>生词高亮
+    <input type="checkbox" id="readCheckbox" onclick="onReadClick()"/>大声朗读
+    <input type="checkbox" id="chooseCheckbox" onclick="onChooseClick()"/>划词入库
     <div class="range">
         <div class="field">
             <div class="sliderValue">
@@ -97,8 +144,8 @@
     <p><b>收集生词吧</b> （可以在正文中划词，也可以复制黏贴）</p>
     <form method="post" action="/{{ username }}/userpage">
         <textarea name="content" id="selected-words" rows="10" cols="120"></textarea><br/>
-        <input type="submit" value="把生词加入我的生词库"/>
-        <input type="reset" value="清除"/>
+        <button class="btn btn-primary btn-lg" type="submit" onclick="Reader.stopRead()">把生词加入我的生词库</button>
+        <button class="btn btn-primary btn-lg" type="reset" onclick="clearSelectedWords()">清除</button>
     </form>
     {% if session.get['thisWord'] %}
         <script type="text/javascript">
@@ -113,7 +160,7 @@
 
     {% if d_len > 0 %}
         <p>
-            <b>我的生词簿</b> 
+            <b>我的生词簿</b>
             <label for="move_dynamiclly">
                 <input type="checkbox" name="move_dynamiclly" id="move_dynamiclly" checked>
                 允许动态调整顺序
@@ -126,9 +173,10 @@
                 {% set freq = x[1] %}
                 {% if session.get('thisWord') == x[0] and session.get('time') == 1 %}
                 {% endif %}
-                <p id='p_{{ word }}' class="new-word" >
-                    <a id="word_{{ word }}"  class="btn btn-light" href='http://youdao.com/w/eng/{{ word }}/#keyfrom=dict2.index'
-                    role="button">{{ word }}</a>
+                <p id='p_{{ word }}' class="new-word">
+                    <a id="word_{{ word }}" class="btn btn-light"
+                       href='http://youdao.com/w/eng/{{ word }}/#keyfrom=dict2.index'
+                       role="button">{{ word }}</a>
                     ( <a id="freq_{{ word }}" title="{{ word }}">{{ freq }}</a> )
                     <a class="btn btn-success" onclick="familiar('{{ word }}')" role="button">熟悉</a>
                     <a class="btn btn-warning" onclick="unfamiliar('{{ word }}')" role="button">不熟悉</a>
@@ -147,60 +195,127 @@
     {% endfor %}
 {% endif %}
 <script type="text/javascript">
-    function load_next_article(){
+    window.onload = function () { // 页面加载时执行
+        const settings = {
+            // initialize settings from localStorage
+            highlightChecked: localStorage.getItem('highlightChecked') !== 'false', // localStorage stores strings, default to true. same below
+            readChecked: localStorage.getItem('readChecked') !== 'false',
+            chooseChecked: localStorage.getItem('chooseChecked') !== 'false',
+            rangeValue: localStorage.getItem('rangeValue') || '1',
+            selectedWords: localStorage.getItem('selectedWords') || ''
+        };
+
+        const elements = {
+            highlightCheckbox: document.querySelector('#highlightCheckbox'),
+            readCheckbox: document.querySelector('#readCheckbox'),
+            chooseCheckbox: document.querySelector('#chooseCheckbox'),
+            rangeComponent: document.querySelector('#rangeComponent'),
+            rangeValueDisplay: document.querySelector('#rangeValue'),
+            selectedWordsInput: document.querySelector('#selected-words')
+        };
+        // 应用设置到页面元素
+        elements.highlightCheckbox.checked = settings.highlightChecked;
+        elements.readCheckbox.checked = settings.readChecked;
+        elements.chooseCheckbox.checked = settings.chooseChecked;
+        elements.rangeComponent.value = settings.rangeValue;
+        elements.rangeValueDisplay.textContent = `${settings.rangeValue}x`;
+        elements.selectedWordsInput.value = settings.selectedWords;
+
+        // 刷新页面或进入页面时判断，若不是首篇文章，则上一篇按钮可见
+        if (sessionStorage.getItem('pre_page_button') !== 'display' && sessionStorage.getItem('pre_page_button')) {
+            $('#load_pre_article').show();
+        }
+
+        // 事件监听器
+        elements.selectedWordsInput.addEventListener('input', () => {
+            localStorage.setItem('selectedWords', elements.selectedWordsInput.value);
+        });
+
+        elements.rangeComponent.addEventListener('input', () => {
+            const rangeValue = elements.rangeComponent.value;
+            elements.rangeValueDisplay.textContent = `${rangeValue}x`;
+            localStorage.setItem('rangeValue', rangeValue);
+        });
+    };
+
+    function clearSelectedWords() {
+        localStorage.removeItem('selectedWords');
+        document.querySelector('#selected-words').value = '';
+    }
+
+
+    function load_next_article() {
+        $("#load_next_article").prop("disabled", true)
         $.ajax({
             url: '/get_next_article/{{username}}',
             dataType: 'json',
-            success: function(data) {
+            success: function (data) {
                 // 更新页面内容
-                if(data['today_article']){
+                if (data['today_article']) {
                     update(data['today_article']);
                     check_pre(data['visited_articles']);
                     check_next(data['result_of_generate_article']);
                 }
+            }, complete: function (xhr, status) {
+                $("#load_next_article").prop("disabled", false)
             }
         });
     }
-    function load_pre_article(){
+
+    function load_pre_article() {
         $.ajax({
             url: '/get_pre_article/{{username}}',
             dataType: 'json',
-            success: function(data) {
+            success: function (data) {
                 // 更新页面内容
-                if(data['today_article']){
+                if (data['today_article']) {
                     update(data['today_article']);
                     check_pre(data['visited_articles']);
                 }
             }
         });
     }
-    function update(today_article){
-        $('#user-level').html(today_article['user_level']);
+
+    function update(today_article) {
+        $('#user_level').html(today_article['user_level']);
         $('#text_level').html(today_article["text_level"]);
-        $('#date').html('Article added on: '+today_article["date"]);
+        $('#date').html('Article added on: ' + today_article["date"]);
         $('#article_title').html(today_article["article_title"]);
         $('#article').html(today_article["article_body"]);
         $('#source').html(today_article['source']);
         $('#question').html(today_article["question"]);
         $('#answer').html(today_article["answer"]);
+        document.querySelector('#text_level').classList.add('mark'); // highlight text difficult level for 2 seconds
+        setTimeout(() => {
+            document.querySelector('#text_level').classList.remove('mark');
+        }, 2000);
+        document.querySelector('#user_level').classList.add('mark'); // do the same thing for user difficulty level
+        setTimeout(() => {
+            document.querySelector('#user_level').classList.remove('mark');
+        }, 2000);
     }
-<!-- 检查是否存在上一篇或下一篇，不存在则对应按钮隐藏-->
-    function check_pre(visited_articles){
-        if((visited_articles=='')||(visited_articles['index']<=0)){
+
+    <!-- 检查是否存在上一篇或下一篇，不存在则对应按钮隐藏-->
+    function check_pre(visited_articles) {
+        if ((visited_articles == '') || (visited_articles['index'] <= 0)) {
             $('#load_pre_article').hide();
-        }else{
+            sessionStorage.setItem('pre_page_button', 'display')
+        } else {
             $('#load_pre_article').show();
+            sessionStorage.setItem('pre_page_button', 'show')
         }
     }
-    function check_next(result_of_generate_article){
-        if(result_of_generate_article == "found"){
-            $('#found').show();$('#not_found').hide();
+
+    function check_next(result_of_generate_article) {
+        if (result_of_generate_article == "found") {
+            $('#found').show();
+            $('#not_found').hide();
             $('#read_all').hide();
-        }else if(result_of_generate_article == "not found"){
+        } else if (result_of_generate_article == "not found") {
             $('#found').hide();
             $('#not_found').show();
             $('#read_all').hide();
-        }else{
+        } else {
             $('#found').hide();
             $('#not_found').hide();
             $('#read_all').show();
diff --git a/app/test/test_next_article.py b/app/test/test_next_article.py
new file mode 100644
index 0000000..3e470de
--- /dev/null
+++ b/app/test/test_next_article.py
@@ -0,0 +1,85 @@
+''' Contributed by Lin Junhong et al. 2023-06.'''
+
+from selenium import webdriver
+from selenium.webdriver.common.desired_capabilities import DesiredCapabilities
+
+from selenium.webdriver.support.ui import WebDriverWait
+from selenium.webdriver.support import expected_conditions as EC
+from selenium.common.exceptions import UnexpectedAlertPresentException, NoAlertPresentException
+import random, time
+import string
+
+# 初始化webdriver
+# driver = webdriver.Remote('http://localhost:4444/wd/hub', DesiredCapabilities.CHROME)
+# driver.implicitly_wait(10)
+driver = webdriver.Chrome("C:\\Users\\12993\AppData\Local\Programs\Python\Python38\\chromedriver.exe")
+
+
+def test_next_article():
+    try:
+        driver.get("http://118.25.96.118:90")
+        assert 'English Pal -' in driver.page_source
+        # login
+        elem = driver.find_element_by_link_text('登录')
+        elem.click()
+
+        uname = 'abcdefg'
+        password = 'abcdefg'
+        elem = driver.find_element_by_id('username')
+        elem.send_keys(uname)
+
+        elem = driver.find_element_by_id('password')
+        elem.send_keys(password)
+        elem = driver.find_element_by_xpath('/html/body/div/button')  # 找到登录按钮
+        elem.click()
+
+        time.sleep(0.5)
+        assert 'EnglishPal Study Room for ' + uname in driver.title
+        for i in range(50):
+            time.sleep(0.1)
+            # 找到固定按钮
+            elem = driver.find_element_by_xpath('//*[@id="load_next_article"]')
+            elem.click()
+    except Exception as e:
+        print(e)
+
+
+def test_local_next_article():
+    try:
+        driver.get("http://127.0.0.1:5000")
+        assert 'English Pal -' in driver.page_source
+        # login
+        elem = driver.find_element_by_link_text('注册')
+        elem.click()
+
+        uname = 'abcdefg'
+        password = 'abcdefg'
+        elem = driver.find_element_by_id('username')
+        elem.send_keys(uname)
+
+        elem = driver.find_element_by_id('password')
+        elem.send_keys(password)
+
+        elem = driver.find_element_by_id('password2')
+        elem.send_keys(password)
+
+        time.sleep(0.5)
+
+        elem = driver.find_element_by_class_name('btn')  # 找到提交按钮
+        elem.click()
+        time.sleep(0.5)
+        try:
+            WebDriverWait(driver, 1).until(EC.alert_is_present())
+            driver.switch_to.alert.accept()
+        except (UnexpectedAlertPresentException, NoAlertPresentException):
+            pass
+
+        time.sleep(0.5)
+        assert 'EnglishPal Study Room for ' + uname in driver.title
+        for i in range(50):
+            time.sleep(0.1)
+            # 找到固定按钮
+            elem = driver.find_element_by_xpath('//*[@id="load_next_article"]')
+            elem.click()
+    except Exception as e:
+        print(e)
diff --git a/requirements.txt b/requirements.txt
index 338b71c..4b81c20 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,5 +1,8 @@
-Flask==1.1.2
+Flask==2.0.3
 selenium==3.141.0
 PyYAML~=6.0
 pony==0.7.16
 snowballstemmer==2.2.0
+Werkzeug==2.2.2
+
+pytest~=8.1.1
\ No newline at end of file
