PayPal Integration: Payment box is too small

I used PayPal Integration with a user defined amount then to get the total from a specified field. When I test it out on the published site the payment box field is too small and does not show the whole total (without clicking into the box and moving left to right). I looked for a way to increase the width, like I can with lots of other features, but I cannot find a way to make it bigger.

Also, is it possible to make this amount a read-only number so the customers cannot change it?

Thanks

1) I used PayPal Integration with a user defined amount then to get the total from a specified field. When I test it out on the published site the payment box field is too small and does not show the whole total (without clicking into the box and moving left to right). I looked for a way to increase the width, like I can with lots of other features, but I cannot find a way to make it bigger.

Add this CSS code:

#input_143_donation{

  width:210px !important;

}

How-to-Inject-Custom-CSS-Codes

2) Also, is it possible to make this amount a read-only number so the customers cannot change it?

#input_143_donation{

  -webkit-user-select: none;

  -moz-user-select: none;

  -ms-user-select: none;

  user-select: none;

}