diff --git a/index.html b/index.html
index b3a57dc..aadb035 100644
--- a/index.html
+++ b/index.html
@@ -2,7 +2,7 @@
 <html lang="zh-CN">
   <head>
     <meta charset="UTF-8">
-    <link rel="icon" href="/logo/logo1.png">
+    <!-- <link rel="icon" href="/logo/logo1.png"> -->
     <meta name="viewport" content="width=device-width, initial-scale=1.0">
     <title>在线学习平台</title>
     <meta name="description" content="专业的在线学习平台，提供优质的编程和技术课程">
diff --git a/src/components/layout/AppFooter.vue b/src/components/layout/AppFooter.vue
index 27d5f11..f14cbd4 100644
--- a/src/components/layout/AppFooter.vue
+++ b/src/components/layout/AppFooter.vue
@@ -3,11 +3,11 @@
     <div class="footer-content">
       <!-- 左侧内容区域 -->
       <div class="footer-left">
-        <!-- 上层：Logo图标 -->
+        <!-- 上层：Logo图标
         <div class="footer-logos">
           <img src="/logo/logo2.png" alt="Logo 1" class="footer-logo-img" />
           <img src="/logo/logo3.png" alt="Logo 2" class="footer-logo-img" />
-        </div>
+        </div> -->
         <!-- 下层：标题文字 -->
         <div class="footer-title">
           {{ t('footer.title') }}
@@ -21,9 +21,9 @@
       <div class="footer-right">
         <div class="certification-section">
           <!-- 认证标志 -->
-          <div class="certification-logo">
+          <!-- <div class="certification-logo">
             <img src="/logo/logo4.png" alt="认证标志" class="cert-logo-img" />
-          </div>
+          </div> -->
           <!-- 认证信息 -->
           <div class="certification-info">
             <div class="cert-line">
diff --git a/src/components/layout/AppHeader.vue b/src/components/layout/AppHeader.vue
index 2e9e1f9..3fdf8aa 100644
--- a/src/components/layout/AppHeader.vue
+++ b/src/components/layout/AppHeader.vue
@@ -2,9 +2,9 @@
   <div class="header-container">
     <!-- Logo区域 -->
     <div class="logo-section">
-      <div class="logo" @click="$router.push('/')">
+      <!-- <div class="logo" @click="$router.push('/')">
         <img src="/logo/logo1.png" alt="Logo" class="logo-image" />
-      </div>
+      </div> -->
     </div>
 
     <!-- 导航菜单 -->
diff --git a/src/views/CourseExchanged.vue b/src/views/CourseExchanged.vue
index 332013e..a1c4efb 100644
--- a/src/views/CourseExchanged.vue
+++ b/src/views/CourseExchanged.vue
@@ -294,8 +294,7 @@
                       @danmaku-send="onDanmakuSend"
                       @qualityChange="onQualityChange"
                     />
-                    <div v-else class="video-placeholder"
-                      :style="{ backgroundImage: course?.coverImage || course?.thumbnail ? `url(${course.coverImage || course.thumbnail})` : '' }">
+                    <div v-else class="video-placeholder" style="background-image: url('/images/aiCompanion/背景色@2x.png');">
                       <div class="placeholder-content">
                         <div class="play-icon">
                           <svg width="60" height="60" viewBox="0 0 60 60">
@@ -4196,12 +4195,46 @@ onActivated(() => {
   display: flex;
   align-items: center;
   justify-content: center;
-  background-color: #f5f5f5;
+  overflow: hidden;
+  /* 如果没有背景图片，使用默认渐变背景 */
+  background-image:
+    radial-gradient(ellipse at 30% 40%, rgba(59, 130, 246, 0.4) 0%, transparent 50%),
+    radial-gradient(ellipse at 70% 60%, rgba(34, 197, 94, 0.3) 0%, transparent 50%),
+    radial-gradient(ellipse at 50% 80%, rgba(168, 85, 247, 0.2) 0%, transparent 50%),
+    linear-gradient(135deg, #1e3a8a 0%, #1e40af 30%, #1d4ed8 60%, #2563eb 100%);
+}
+
+.video-placeholder::before {
+  content: '';
+  position: absolute;
+  top: 0;
+  left: 0;
+  right: 0;
+  bottom: 0;
+  background-image: url('/images/aiCompanion/bg.png');
+  background-size: cover;
+  background-position: center;
+  background-repeat: no-repeat;
+}
+
+.video-placeholder::after {
+  content: '';
+  position: absolute;
+  top: 0;
+  left: 0;
+  right: 0;
+  bottom: 0;
+  background:
+    radial-gradient(ellipse 800px 600px at 40% 50%, rgba(59, 130, 246, 0.08) 0%, transparent 70%),
+    radial-gradient(ellipse 600px 400px at 60% 30%, rgba(34, 197, 94, 0.06) 0%, transparent 70%);
+  pointer-events: none;
 }
 
 .placeholder-content {
+  position: relative;
+  z-index: 2;
   text-align: center;
-  color: #666;
+  color: white;
 }
 
 .play-icon {
diff --git a/src/views/Home.vue b/src/views/Home.vue
index 110dfcd..71bf4e7 100644
--- a/src/views/Home.vue
+++ b/src/views/Home.vue
@@ -4,7 +4,7 @@
     <section class="hero-banner">
       <img :src="bannerImage" :alt="bannerAlt" class="banner-image" />
       <div class="hero-content">
-        <h2>{{ mainTitle }}<span>{{ mainTitleHighlight }}</span>在线学习平台</h2>
+        <h2>云南省{{ mainTitle }}<span>{{ mainTitleHighlight }}</span>在线学习平台</h2>
         <p>为教师量身定制，帮助教师快速掌握AI技术、教学应用与伦理规范，赋能智慧课堂</p>
         <button @click="goToCoursesPage">立即学习</button>
       </div>
diff --git a/src/views/teacher/ExamPages/ExamLibrary.vue b/src/views/teacher/ExamPages/ExamLibrary.vue
index b517bd3..6840265 100644
--- a/src/views/teacher/ExamPages/ExamLibrary.vue
+++ b/src/views/teacher/ExamPages/ExamLibrary.vue
@@ -118,12 +118,6 @@ const createColumns = ({
         {
             type: 'selection',
         },
-        {
-            title: '序号',
-            key: 'id',
-            width: 60,
-            align: 'center',
-        },
         {
             title: '试卷名称',
             key: 'name',
