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

page {
    background: white;
    display: block;
    margin: 0 auto;
    margin-bottom: 0.5cm;
    box-shadow: 0 0 0.5cm rgba(0,0,0,0.5);
}

    page[size="A4"] {
        width: 21cm;
        height: 29.7cm;
    }

        page[size="A4"][layout="landscape"] {
            width: 29.7cm;
            height: 21cm;
        }

    page[size="A3"] {
        width: 29.7cm;
        height: 42cm;
    }

        page[size="A3"][layout="landscape"] {
            width: 42cm;
            height: 29.7cm;
        }

    page[size="A5"] {
        width: 14.8cm;
        height: 21cm;
    }

        page[size="A5"][layout="landscape"] {
            width: 21cm;
            height: 14.8cm;
        }

@media print {
    body, page {
        margin: 0;
        box-shadow: 0;
        -webkit-print-color-adjust: exact;
    }
}