how to make toga.webview video full screen?

Question

briefcase dev

it can't full screen like chrome the fllow is my code

"""
影视采集测试
"""
        main_box = toga.Box(style=Pack(direction=COLUMN))
        self.webview = toga.WebView(style=Pack(flex=1))
        main_box.add(self.webview)

        control_box = toga.Box(style=Pack(direction=ROW))
        button = toga.Button('播放', on_press=self.video_play)
        control_box.add(button)
        
        main_box.add(control_box)
        self.main_window = toga.MainWindow(title=self.formal_name)
        self.main_window.content = main_box
        self.main_window.show()
    async def video_play(self,widget):
        self.webview.url = "https://jx.wujinkk.com/dplayer/?url=https://top.1080pzy.co/202311/07/q311g19B863/video/index.m3u8"

i want to make it full screen