/* couleur de la couverture */

:root{
    --couleur: rgb(255, 90, 90);
}

/* motif de bordure généré avec maxbittker.github.io/broider/ */

.couverture,
header {
    border-image:  url("data:image/png;base64,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") 28 /  28px / 0 round;
    border-width:  28px;
    border-style:  solid;
}