How do I change the close window color and the transparency of the windows?

[Calvinnncy97]

Hi, thank you for the great theme! It is my favorite theme but I have some questions tweaking it. Hope you can enlighten me!

May I know how can I change the close window button? I found a lot of svg files of the same close window button in different folders but I do not know which one to change.

Besides, I realize the left panel of my window is semi-transparent while my right panel is not. I am trying to increase the transparency and also to make the right panel transparent. But I can't find the right file (and the right properties) to change.

By left panel, I mean the panel that displays folders such as 'Home', 'Downloads' etc. By right panel I meant the panel directly beside the left panel.

Hope you can help. Thank you so much!

Best regards,
Calvinn