Adding classes for Luxe Checkout Add-on Compatibility for PayStack Payment Module located on modules/Paystack/Resources/views/button.blade.php

button.blade.php

<div class="text-center payment_form_submiter" id="paystack-payment-form" style="display: {{ config('settings.default_payment')=="paystack"?"block":"none"}};" >
    <button
        v-if="totalPrice"
        type="submit"
        class="button full-button d-flex align-items-center justify-content-center uppercase paymentbutton"
        onclick="this.disabled=true;this.form.submit();"
    >{{ __('Place order') }}</button>
</div>