body {
  background: rgb(204,204,204);
}

page[size="A4"] {
  background-image: url("bg_full_a4_1.png");
  background-size: 100%;
  background-repeat: no-repeat;
  width: 21cm;
  height: 29.7cm;
  display: block;
  margin: 0 auto;
  margin-bottom: 0.5cm;
  box-shadow: 0 0 0.5cm rgba(0,0,0,0.5);
}

@media print {
  body, page[size="A4"] {
    margin: 0;
    box-shadow: 0;
  }