How do I make health bar increase and decrease on click?

Hello everyone. I followed this neat tutorial on you tube and made this health bar. The trouble is i can seem to get around how to increase the bar and maintain the opacity transition. I have a capx maybe that can help dropbox.com/s/ahq9iicasxz5znk/health%20bar%20increase.capx

This can be done a bit easier:

dropbox.com/s/49f20g1vdfcp4jf/HealthBar.capx

Thank you very much, is there a way i can attach a global variable or instance to each each step or color change

I used instance variable, but you can change it to global variable if you want.

Thank you very much again