REMOVE: Xóa fallback exportExcel() - chỉ gọi VAI_QR.exportExcel() trực tiếp

index.html

@@ -749,7 +749,7 @@ textarea.form-input{height:120px;resize:vertical}
 <div class="quote-actions">
 <button class="quote-btn" onclick="shareQuoteImage()" style="background:#25D366"><i class="fas fa-share-alt"></i> Chia sẻ ảnh</button>  
 <button class="quote-btn" onclick="shareQuoteLink()" style="background:#0068FF"><i class="fas fa-share-alt"></i> Chia sẻ báo giá</button>  
-<button class="quote-btn quote-btn-excel" onclick="window.VAI_QR && VAI_QR.exportExcel ? VAI_QR.exportExcel() : exportExcel()"><i class="fas fa-file-excel"></i> Xuất Excel</button>
+<button class="quote-btn quote-btn-excel" onclick="VAI_QR.exportExcel()"><i class="fas fa-file-excel"></i> Xuất Excel</button>
 <button class="quote-btn quote-btn-pdf" onclick="exportPDF()"><i class="fas fa-file-pdf"></i> Xuất PDF</button>
 <label class="quote-btn" style="background:#fff;color:#111;border:1px solid #111"><input id="vai-bw-export" type="checkbox" style="width:16px;height:16px;margin-right:6px"> Trắng đen</label>
 <button class="quote-btn quote-btn-print" onclick="printQuotation()"><i class="fas fa-print"></i> In báo giá</button>