fix: 修复遮罩错误问题

src/component/Canvas/canvasExample.vue

@@ -182,13 +182,13 @@ const isShowLeft = ref(true);
 <template>
   <div class="app-container-example">
     <!-- 模拟左侧导航栏 -->
-    <div
+    <!-- <div
       class="app-wrapper-btns"
       :class="{ hide: !isShowLeft }"
       @click="isShowLeft = !isShowLeft"
     >
       <div class="app-btn">收起/展开</div>
-    </div>
+    </div> -->
     <!-- 内容区域 -->
     <div class="app-content">
       <!-- 红绿图模式示例 -->