@media print {
  body > *:not(#print-area) { display: none !important; }
  #print-area { display: block !important; font-family: monospace; font-size: 12px; width: 80mm; margin: 0; padding: 4mm; }
  #print-area h1 { font-size: 16px; text-align: center; margin: 0 0 4px; }
  #print-area .sep { border-top: 1px dashed #000; margin: 6px 0; }
  #print-area .row { display: flex; justify-content: space-between; }
  #print-area .center { text-align: center; }
  @page { margin: 2mm; size: 80mm auto; }
}