fix: pdf backgorund

src/components/md-deck/hooks/usePDFExport.ts

@@ -75,7 +75,7 @@ async function renderCardToCanvas(card: PageCard, options: ExportOptions): Promi
   gridContainer.style.height = `${gridAreaHeight}mm`;
 
   for (const layer of visibleLayers) {
-    const layerEl = document.createElement('div');
+    const layerEl = document.createElement('article');
     layerEl.className = 'absolute flex items-center justify-center text-center prose prose-sm';
     Object.assign(layerEl.style, getLayerStyle(layer, dimensions));
     layerEl.style.fontSize = `${fontSize}mm`;
@@ -92,7 +92,7 @@ async function renderCardToCanvas(card: PageCard, options: ExportOptions): Promi
       scale: 2,
       backgroundColor: null,
       logging: false,
-      useCORS: true
+      useCORS: true,
     });
   } finally {
     document.body.removeChild(container);