:root{--background:#f8fafc;--foreground:#0f172a;--border:#e2e8f0;--muted:#64748b;--up:#15803d;--down:#b91c1c;--surface:#fff}*{box-sizing:border-box}body{background:var(--background);color:var(--foreground);margin:0;font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Helvetica,Arial,sans-serif}