body{margin:0;font-family:system-ui,-apple-system,"Segoe UI",Roboto,sans-serif;background:#f7f9fc;}
.qr-shell{max-width:1600px;margin:0 auto;padding:24px 16px;}
.qr-block{margin-bottom:20px;}
.qr-row{display:flex;gap:20px;flex-wrap:wrap;}
.qr-row .qr-block{flex:1 1 300px;margin-bottom:0;}