:root{--bg:#f7fafc;--card:#fff;--accent:#0f172a;--muted:#6b7280;--accent-2:#2563eb}*{box-sizing:border-box}body{font-family:Inter,ui-sans-serif,system-ui,-apple-system,Segoe UI,Roboto,Helvetica Neue,Arial;margin:0;background:var(--bg);color:var(--accent);padding:20px}.app{max-width:900px;margin:0 auto}header h1{margin:0 0 4px}header p{margin:0 0 12px;color:var(--muted)}.controls{background:#fff;padding:12px;border-radius:8px;box-shadow:0 1px 3px #0206170f;margin-bottom:16px}.controls label{display:block;margin-bottom:8px}.controls input[type=number]{margin-left:8px;padding:6px;border:1px solid #e5e7eb;border-radius:6px;width:160px}.btn-row{display:flex;gap:8px;flex-wrap:wrap;margin:8px 0}button{background:var(--accent-2);color:#fff;border:none;padding:8px 12px;border-radius:8px;cursor:pointer}button:disabled{opacity:.5;cursor:not-allowed}.toggles{display:flex;gap:12px;flex-wrap:wrap;align-items:center;margin-top:8px}.toggles label{font-size:14px;color:var(--muted)}.main{min-height:200px}.placeholder{background:#fff;padding:40px;border-radius:8px;text-align:center;color:var(--muted)}.card{background:var(--card);padding:18px;border-radius:12px;box-shadow:0 6px 18px #0206170f;display:flex;flex-direction:column;align-items:center}.card-top{display:flex;gap:16px;align-items:baseline}.arabic,.thai-numeral{font-size:36px;font-weight:700}.num-sep{font-size:20px;color:var(--muted);align-self:center}.card-body{margin-top:12px;text-align:center}.thai-words{font-size:28px;font-weight:600}.romanization{margin-top:6px;color:var(--muted)}.hidden-answer{font-size:32px;color:#cbd5e1;padding:18px}footer{margin-top:16px;color:var(--muted);display:flex;justify-content:space-between;align-items:center;flex-wrap:wrap;gap:8px}