refactor(AdOverlay): 移除滚动容器并优化关闭按钮样式

将广告图片容器从 scroll-view 改为普通 view 以简化结构
调整关闭按钮位置和样式，增加背景模糊效果

@@ -7,10 +7,9 @@
   >
     <view class="overlay-body">
       <view class="overlay-content">
-        <!-- 广告图片容器 - 支持滚动 -->
-        <scroll-view
-          class="ad-scroll-container"
-          scroll-y
+        <!-- 广告图片容器 -->
+        <view
+          class="ad-image-container"
           @tap="handleAdClick"
         >
           <image
@@ -19,11 +18,11 @@
             class="ad-image"
             alt="广告图片"
           />
-        </scroll-view>
+        </view>
 
         <!-- 关闭按钮 -->
         <view class="close-button" @tap="handleClose">
-          <Close size="24" class="close-icon" />
+          <Close size="16" class="close-icon" />
         </view>
       </view>
     </view>
@@ -52,6 +51,7 @@ const emit = defineEmits(['close', 'click'])
 
 // 响应式数据
 const visible = ref(false)
+const showCloseButton = ref(true)
 
 /**
  * 获取今天的日期字符串（YYYY-MM-DD格式）
@@ -194,6 +194,7 @@ onMounted(async () => {
   justify-content: center;
   padding: 40rpx;
   box-sizing: border-box;
+  position: relative;
 }
 
 .overlay-content {
@@ -204,46 +205,46 @@ onMounted(async () => {
   width: 80vw;
   max-width: 600rpx;
   height: 100%;
-  max-height: calc(100vh - 80rpx);
+  position: relative;
 }
 
-.ad-scroll-container {
+.ad-image-container {
   width: 100%;
-  max-height: calc(100vh - 200rpx); // 预留关闭按钮和间距的空间
   border-radius: 16rpx;
   overflow: hidden;
   box-shadow: 0 8rpx 32rpx rgba(0, 0, 0, 0.3);
   cursor: pointer;
-  margin-bottom: 40rpx;
-  // 移除背景色，避免白边
-  // background-color: #fff;
+  position: relative;
 }
 
 .ad-image {
   width: 100%;
   display: block;
-  min-height: 200rpx; // 设置最小高度
-  // 移除图片的圆角，让容器的圆角生效
+  min-height: 200rpx;
   border-radius: 16rpx;
-  // 确保图片完全填充容器
   object-fit: cover;
-  // 移除可能的边距和边框
   margin: 0;
   padding: 0;
   border: none;
-  // 确保图片垂直对齐
   vertical-align: top;
 }
 
 .close-button {
-  width: 60rpx;
-  height: 60rpx;
+  position: fixed;
+  bottom: 60rpx;
+  left: 50%;
+  transform: translateX(-50%);
+  width: 80rpx;
+  height: 80rpx;
+  background-color: rgba(0, 0, 0, 0.6);
   border-radius: 50%;
   display: flex;
   align-items: center;
   justify-content: center;
+  z-index: 1001;
+  backdrop-filter: blur(10rpx);
   cursor: pointer;
-  flex-shrink: 0; // 防止被压缩
+  flex-shrink: 0;
 }
 
 .close-icon {
@@ -251,7 +252,7 @@ onMounted(async () => {
 }
 
 /* 点击效果 */
-.ad-scroll-container:active {
+.ad-image-container:active {
   transform: scale(0.98);
   transition: transform 0.1s ease;
 }