Also, some feedback:
⇒ The win condition is unclear—you just win or lose spontaneously seemingly without reason.
⇒ The fact you can reinforce with cards of the same SUIT needs to be clearer.
⇒ The little indicators showing what cards are on the field should return to "x" after a battle is won.
⇒ It would be very helpful to be able to see the opponent's play field and how many cards they have in their hand.