:root{color-scheme:light;font-family:IBM Plex Sans,Segoe UI,sans-serif;background:#f3f4f6;color:#111827}*{box-sizing:border-box}body{margin:0}.shell{min-height:100vh;display:grid;place-items:center;padding:2rem;background:radial-gradient(circle at 10% 20%,#fef3c7 0%,transparent 35%),radial-gradient(circle at 90% 85%,#dbeafe 0%,transparent 30%),#f3f4f6}.card{width:min(720px,100%);border-radius:16px;background:#fff;padding:2rem;box-shadow:0 12px 30px #1118271f}h1{margin:0 0 1rem}