title: How to set border color of certain Tkinter widgets?
body: <p>I'm trying to change the background color of my Tkinter app, but for certain widgets it leaves a white border around the edges.</p>
  
  <p>For example, this:</p>
  
  <pre><code>from tkinter import *
  
  COLOR = "black"
  
  root = Tk()
  root.config(bg=COLOR)
  
  button = Button(text="button", bg=COLOR)
  button.pack(padx=5, pady=5)
  entry = Entry(bg=COLOR, fg='white')
  entry.pack(padx=5, pady=5)
  text = Text(bg=COLOR, fg='white')
  text.pack(padx=5, pady=5)
  
  root.mainloop()
  </code></pre>
  
  <p>How can I set border colour of certain Tkinter widgets?</p>