[Tkinter] TKinter Remove Button Frame

[Nu2Python]

Hi All - How can I remove the button frame in my code? I have tried a few examples I found, but have had no luck. I see one argument example for 'borderwidth=0' but does not seem to change anything. I am using a toggle button with images. Attached picture is what I have showing for my button. The image has rounded corners, so I want to remove the frame of the button completely. Thanks for any help with this.

import tkinter as tk
from tkinter import *
from tkinter import messagebox
import requests
import http.client
import time
import json
   
path = ""

SONOFF_Temp  = 'http://192.168.0.130/cm?cmnd=status+10'
sonoff_url = 'NOT_INIT'


class RelayButton(tk.Button):
    """A button that toggles a relay"""
    def __init__(self, parent, url="", on_image=None, off_image=None, **kwargs):
        super().__init__(parent, image=off_image, command=self.toggle)
        self.url = url
        self._on = False
        self.on_image = on_image
        self.off_image = off_image
        self.label = Label(text="", bg="White", fg="Black", font=("Helvetica", 12))
        self.label.place(x=10,y=15)
        self.update_clock()
        self.templabel = Label(text="temp info", bg="White", fg="Black", font=("Helvetica", 12))
        self.templabel.place(x=10, y=40)
        #self.getTemp()
        self.master.configure(background="white")
        
    @property
    def on(self):
        """Return state of the relay"""
        return self._on
   
    @on.setter
    def on(self, on):
        """Set state of the relay"""
        
        self._on = on

        try:
            if on:
                requests.post(f"{self.url}cm?cmnd=Power On")
                self["image"] = self.on_image
            else:
                requests.post(f"{self.url}cm?cmnd=Power Off")
                self["image"] = self.off_image
        except:
            messagebox.showinfo("Error")
    def toggle(self):
        """Toggle state of the relay"""
        self.on = not self.on
        
    def update_clock(self):
        now = time.strftime("%I:%M:%S %p " + ' - ' + "%x")
        self.label.configure(text='Time/Date:  ' + now)
        self.after(1000, self.update_clock)
        
    def getTemp(self):
        sonoff_url = SONOFF_Temp
        sonR1 = requests.get(sonoff_url)
        x = json.loads(sonR1.text)
        status = x["StatusSNS"]
        timestamp = status["Time"]
        device_names = list(status.keys())[1:-1]
        temp_units = status["TempUnit"]
        
        for name in device_names:
            device = status[name]
            #print(f'ID={name}, Temperature={device["Temperature"]} {temp_units}')
            self.templabel.configure(text='Living Room '+f'Temperature: {device["Temperature"]} {temp_units}')
            self.after(5000, self.getTemp)
            
   
def new_button(name, url, parent, row, column, **kwargs):
    """Convenience functon that creates a RelayButton"""
    on_image = tk.PhotoImage(file=f"{path}{name}_on.png")
    off_image = tk.PhotoImage(file=f"{path}{name}_off.png")
    button = RelayButton(parent, url, on_image, off_image, **kwargs)
    button.grid(row=row, column=column, padx=70, pady=110)
    return button


   
def main():
    app = tk.Tk()
    app.title('Home Relay Control')
    buttons = [
        #new_button('lvgRoom', "http://192.168.0.101/", app, 0, 0),
        new_button('frPorch', "http://192.168.0.130/", app, 0, 1)
        ]
    
    for b in buttons:
        b.on = False
    app.mainloop()
    
    
if __name__ == "__main__":
    main()