game_v1.kv

BoxLayout:
    orientation: 'vertical'
    GridLayout:
        rows: 3
        cols: 3
        Button:
            text: 'X'
        Button:
            text: 'O'
        Button:
            text: 'X'
        Button:
            text: 'O'
        Button:
            text: 'X'
        Button:
            text: ''
        Button:
            text: 'O'
        Button:
            text: ''
        Button:
            text: 'X'

    Label:
        text_size: self.size
        halign: 'left'
        size_hint_y: 0.1
        text: 'game over...'