*{box-sizing:border-box}body{font-family:system-ui,Arial;margin:0;background:#f6f8fb;color:#172033}.wrap{max-width:980px;margin:auto;padding:24px}.card{background:#fff;border:1px solid #dfe5ee;border-radius:16px;padding:20px;box-shadow:0 8px 25px rgba(20,30,50,.06)}.grid{display:grid;grid-template-columns:1fr 1fr;gap:16px}label{display:block;font-weight:650;margin:10px 0 6px}input{width:100%;padding:11px;border:1px solid #bcc7d6;border-radius:9px}button{margin-top:16px;padding:11px 18px;border:0;border-radius:9px;background:#174ea6;color:#fff;font-weight:700;cursor:pointer}.result{margin-top:18px;padding:16px;border-radius:12px;background:#eef5ff}.muted{color:#5d6878}.formula{font-family:ui-monospace,monospace;background:#f3f5f8;padding:10px;border-radius:8px}@media(max-width:700px){.grid{grid-template-columns:1fr}}@media(prefers-color-scheme:dark){body{background:#10141b;color:#e8edf5}.card{background:#171d27;border-color:#303a49}.result{background:#202b3c}input{background:#111722;color:#fff;border-color:#455166}.muted{color:#aeb8c7}.formula{background:#111722}}