when i add modal in payment method specifically when selecting paypal i wont to show modal and display something in there but it doesnt work. my modal works fine in a fresh php file outside abantecart but when i insert the link href and script src needed to run the modal
it seems to be in conflict with abantecart and changes some colors and my modal wont work.

please help

 Hi, i want to edit subtotal.php to add 8% to the total if the payment method is paypal.

how to make it happen?

please help