Ok I get what you mean now.
I've upgraded your capx a bit. I've added an OK btn for imputing the password (no need of pressing Enter in the keyboard), and now the system uses only one SpriteFont for the numbered Btns and another one for the ok/clear Btns (you can merge those categories into one universal Btn if you wish).
And, finally, there is a mouse cursor change when ever you are hovering on top of a Btn.