fix(editor): make image editor backdrop opaque and prevent home bleed-through

components/image-annotator.tsx

@@ -1380,12 +1380,12 @@ export function ImageAnnotator({
   // 弹窗内容
   const modalContent = (
     <div 
-      className="fixed inset-0 z-[9999] flex items-center justify-center bg-background"
+      className="fixed inset-0 z-[9999] flex items-center justify-center bg-black/55 backdrop-blur-sm"
       onClick={onCancel}
     >
       {/* 弹窗容器 - 全屏显示 */}
       <div 
-        className="flex flex-col overflow-hidden w-full h-full"
+        className="flex h-full w-full flex-col overflow-hidden bg-background"
         onClick={(e) => e.stopPropagation()}
       >
         {/* 顶部标题栏 - 始终深色模式，高度与首页导航栏一致 */}