Quelques pistes pour l'intégration :

https://stackoverflow.com/questions/12609110/responsive-css-background-images

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background-image:url('../images/bg.png');
background-repeat:no-repeat;
background-size:contain;
background-position:center;
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https://www.webfx.com/blog/web-design/responsive-background-image/

https://stackoverflow.com/questions/20009361/css-responsive-background-image-map