How to implement omnipay cybersource package?

I have implement omnipay Cybersource package. Like this

$gateway = \Omnipay\Omnipay::create('Cybersource');

$gateway->initialize(array(
    'profileId' => '',
    'secretKey'   => '',
    'accessKey' => '',
    'testMode' => true, // Or false when you are ready for live transactions
));

$response = $gateway->purchase(
    [
        'amount' => '10.00',
        'currency' => 'USD',
        'card' => [
            'firstName' => 'test'
        ]
    ]
)->send();

if ($response->isSuccessful()) {
    echo "Transaction was successful!\n";
} else if ($response->isRedirect()) {
    $response->redirect();

} else {
    // Payment failed
    echo $response->getMessage();
}

But I didn't get the off-site page to enter the card information details while I run this code. I redirected to success page.