:root{--ink:#0b1b36;--muted:#6b7280;--accent:#667eea}
*{box-sizing:border-box}body{font-family:system-ui,-apple-system,Segoe UI,Roboto,Inter,Arial,sans-serif;margin:0;color:var(--ink);background:#f7f4ed}
.container{max-width:720px;margin:4rem auto;padding:0 1rem}
h1{margin:0 0 .5rem}
.muted{color:var(--muted);margin:0 0 1.5rem}
.grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:1rem;margin-bottom:1rem}
label{display:grid;gap:.35rem}
input{padding:.65rem .75rem;border:1px solid #e5e7eb;border-radius:.5rem;font-size:1rem}
button{background:linear-gradient(135deg,#667eea,#764ba2);color:#fff;border:none;border-radius:.6rem;padding:.7rem 1rem;font-weight:700;cursor:pointer}
button:hover{filter:brightness(1.05)}
output{display:block;margin-top:1rem;padding:1rem;border:1px dashed #e5e7eb;border-radius:.6rem;background:#fff}
.notes{margin-top:1rem;color:var(--muted)}
@media (max-width:640px){.grid{grid-template-columns:1fr}}