different width for bars in stacked bar chart

Dear all, I have a stacked bar chart as you can see in the image below. 

I want the green bar to be either wider or thinner. The other alternative is to have the first colors as kind of transparent so that I can see the green bar below them. 

I don't know how can I do this!! I tried to find custom visuals which can do something like this, but I was not successful. 

So, if you have any suggestions or any workarounds, please let me know.

Regards