title: Tkinter GUI Python background color
body: <p>I'm writing a Tkinter application with buttons, graphs, sliders, etc, but I can't get their background color to be uniform. </p>
  
  <pre><code>import Tkinter
  from Tkinter import *
  root = Tk()
  root.title('Button')
  root.configure(bg='gray')
  
  Button(text='Button', bg='gray').pack(side=BOTTOM)
  root.mainloop()
  </code></pre>
  
  <p>If you run this code, the background of the main window is indeed gray, but the image of the button has a white area around it. Is there a way to fix this?</p>