Is there a way to do this with HTML/CSS or any other coding language that will be supported?
Welcome to the forums!
You could try using CSS3 to create a display:none/display:block effect on your button.
Otherwise, I am not aware of any other method.
Hi tvanderbiltgroup and Frederick, you may want to take a look at our tutorial on progressive disclosure. This technique absolutely won't work in many email clients (it's been designed exclusively for mobile), so no promises it will be of use in this scenario.