:root{color-scheme:dark;font-family:system-ui,-apple-system,Segoe UI,Roboto,sans-serif}*{box-sizing:border-box}body{margin:0}.shell{min-height:100vh;display:grid;place-items:center;background:#0d1117;color:#e6edf3}.card{text-align:center;padding:2.5rem 3rem;border:1px solid #30363d;border-radius:12px;background:#161b22}.card h1{margin:0 0 .5rem;font-size:1.5rem;letter-spacing:.02em}.card p{margin:0;color:#8b949e;text-transform:uppercase;font-size:.8rem;letter-spacing:.15em}