1.0, 'EUR' => 0.92, 'CNY' => 7.21, 'JPY' => 149.5, 'KRW' => 1335.0,
'GBP' => 0.79, 'RUB' => 92.4, 'HKD' => 7.82, 'SGD' => 1.34, 'AUD' => 1.53,
'CAD' => 1.35, 'BRL' => 4.98, 'INR' => 83.0, 'VND' => 24500.0, 'THB' => 35.8,
'MYR' => 4.77, 'IDR' => 15600.0, 'PHP' => 56.1, 'AED' => 3.67, 'TRY' => 31.0
];
$rate = $rates[$currency] ?? 1.0;
$usdt_amount = $amount / $rate;
?>