:root { color-scheme: light dark; font-family: system-ui, -apple-system, Segoe UI, sans-serif; }
body { margin: 0; background: #f4f6f8; color: #17202a; }
header { background: #17202a; color: white; padding: 1.2rem 2rem; }
main { max-width: 1180px; margin: 0 auto; padding: 1.5rem; }
.card { background: white; border-radius: 14px; padding: 1rem; box-shadow: 0 2px 12px rgba(0,0,0,.08); margin-bottom: 1rem; }
.grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(180px, 1fr)); gap: 1rem; }
.metric { font-size: 1.8rem; font-weight: 700; }
label, select { font-size: 1rem; }
select { padding: .45rem; border-radius: 8px; }
canvas { width: 100%; max-height: 360px; }
@media (prefers-color-scheme: dark) { body { background: #0f1419; color: #e6edf3; } .card { background: #17202a; } }