Q:

Tkinter Inverting Color of Radiobutton

Trying to invert the colour of the radiobutton when it has been selected. Currently when the button is not selected the background is grey and foreground white. When it is selected the background goes white but the foreground also stays white. I want to be able to change the colour of the foreground when it has been selected.
import tkinter as tk
root = tk.Tk()
v = tk.IntVar()
v.set(0)

periods = [
    ("Current"), 
    ("-1"), 
    ("-2"), 
    ("1 Week"),
    ("2 Weeks"), 
    ("1 Month"), 
    ("3 Months"), 
]
def ShowChoice():
    print (v.get())

for val, period in enumerate(periods):
    tk.Radiobutton(root, 
              text=period, 
              indicatoron =0,
              padx=20,
              variable=v, 
              command=ShowChoice, 
              value=val,
              background='gray15', 
              foreground='snow',).pack(side=tk.LEFT)
root.mainloop()

This is what the buttons currently look like:

Thanks in advance

A:

All it was is
selectcolor='gray25'

Options for Radiobutton look like this now:
for val, period in enumerate(periods):
    tk.Radiobutton(root, 
              text=period, 
              indicatoron =0,
              padx=20,
              variable=v, 
              command=ShowChoice, 
              value=val,
              background='gray15', 
              foreground='snow',
              selectcolor='gray25').pack(side=tk.LEFT)
root.mainloop()

And the outcome is this:

