style(qrcode): 优化预览态布局适配popup窗口

- 调整文本预览区域高度，单行显示截断文本
- 缩小二维码图片尺寸（56x56 -> 48x48）
- 减少内边距和间距，更紧凑的布局
- 确保完整显示在popup窗口中无需滚动

src/components/QrCodePreview.tsx

@@ -46,34 +46,34 @@ const QrCodePreview = ({
   return (
     <div
       className={cn(
-        'flex flex-col justify-center items-center min-h-[200px] border border-input rounded-xl p-6 bg-muted/40',
+        'flex flex-col justify-center items-center border border-input rounded-xl p-4 bg-muted/40',
         className,
       )}
       {...props}
     >
       <div className="flex flex-col items-center w-full max-w-xs">
         {/*
-          2. 二维码容器适配：
+          二维码容器适配：
           在暗黑模式下，纯黑白的二维码如果直接暴露在暗色背景下，会导致手机摄像头极难识别。
-          通过裹一层 bg-white 和 p-3，确保黑白对比度绝对安全，同时加入 shadow 增强卡片感。
+          通过裹一层 bg-white 和 p-2，确保黑白对比度绝对安全，同时加入 shadow 增强卡片感。
         */}
-        <div className="p-3 bg-white rounded-lg shadow-sm border border-border/40">
+        <div className="p-2 bg-white rounded-lg shadow-sm border border-border/40">
           <img
             src={qrCodeDataUrl}
             alt="QR Code Preview"
-            className="w-56 h-56 max-w-full object-contain block animate-in fade-in duration-300"
+            className="w-48 h-48 max-w-full object-contain block animate-in fade-in duration-300"
           />
         </div>
 
-        <div className="flex w-full gap-2 mt-5">
-          <Button variant="outline" size="sm" onClick={onDownload} className="flex-1">
-            <Download className="w-4 h-4 text-muted-foreground" />
-            <span className="truncate">{t('qrCode:downloadButton')}</span>
+        <div className="flex w-full gap-2 mt-3">
+          <Button variant="outline" size="sm" onClick={onDownload} className="flex-1 h-8">
+            <Download className="w-3.5 h-3.5 text-muted-foreground" />
+            <span className="truncate text-xs">{t('qrCode:downloadButton')}</span>
           </Button>
 
-          <Button variant="default" size="sm" onClick={onCopy} className="flex-1">
-            <Copy className="w-4 h-4" />
-            <span className="truncate">{t('qrCode:copyQrButton')}</span>
+          <Button variant="default" size="sm" onClick={onCopy} className="flex-1 h-8">
+            <Copy className="w-3.5 h-3.5" />
+            <span className="truncate text-xs">{t('qrCode:copyQrButton')}</span>
           </Button>
         </div>
       </div>