It depends how you build your buttons:
I see two solutions:
1. Use Javascript to add or remove additional styles to the buttons, or
2. Build the buttons from a combination of input labels
<input type=”radio” name=”specialButton” class=”specialButtonTriggerStyleClass” id=”specialButton1″>
<label class=”specialButtonStyleClass” for=”specialButton1″>Button 1</label>
<input type=”radio” name=”specialButton” class=”specialButtonTriggerStyleClass” id=”specialButton2″>
<label class=”specialButtonStyleClass” for=”specialButton2″>Button 2</label>
<style>
.specialButtonTriggerStyleClass {
display: none;
}
.specialButtonTriggerStyleClass:checked + .specialButtonStyleClass{
border: 2px solid green;
}
.specialButtonStyleClass {
border: 2px solid red;
}
</style>`
`