Python: Tkinter: How to change the windows border color?
As I see you are using windows.
This color is set by the theme you are currently using. It is the same for every window.
So I cross out the possibility of only using the Tkinter module for this.
Tkinter is responsible for what is in the window but the window manager decides about the border. For example in Ubuntu the window would look totally different.
I guess, you would need some windows specific calls for that.
You can remove the border with root.overrideredirect(1) if I remember correctly.
PS: put "windows" into the tags of this question.