Using templates, how can I make past slides inactive?

[JJ]

In this presentation where I use templates I had to uncomment the css inactive class since all slides in the template appeared as inactive. is there a simple way to make them active when selected using templates, or do I have to set up a trigger?

[JJ]

OK, i got it here

.step { opacity: 0.3; }
.step.nested-active, .step.active, .step.active .step { opacity: 1 }