The top html.Divs cannot touch edge of Chrome

Hi experts,

I have a top Div that looks like this:

html.Div(
                [
                    html.Div(
                        children=[
                            html.I(
                                className="fa fa-bell-o fa-warning",
                                style={
                                    "font-size": "18",
                                    "color": "red",
                                    "display": "inline-block",
                                    "width": "10%",
                                    "text-align": "center",
                                    "float": "right",
                                    "padding": "12 0",
                                }
                            ),
                            html.Img(
                                src='https://raw.githubusercontent.com/markus-zhang/Dragonlance-Editor/master/BART.png',
                                height="50",
                                style={
                                    "float": "left",
                                    "padding": "12 0",
                                    "width": "10%"
                                }
                            )
                        ],
                        style={

                        }
                    ),
                ],
                style={
                    "height": "50",
                    "background-color": "#111",
                    "margin": "0",
                    "padding": "0",
                    "overflow": "auto",
                    "display": "table",
                    "z-index": "1000 !important",
                    "width": "100%"
                }
            ),

The thing is, this is the only Div that cannot touch the edge of screen in Chrome, pretty weird. Here is a screenshot:

I googled and it seems that I need to do a css reset, however I don’t know how to modify css of body in my code, and somehow none of the css I throw into /assets works.