myapp_2_sidebar.py

sidebar = html.Div(
    [   # add some header text
        html.H2("My App", className="display-4", 
                style={'textAlign': 'center', 'font-variant': 'small-caps'}),
        html.Hr(), # this adds a horizontal line
        html.H3( # H3 is a smaller header than H2
            "Data Analytics", className="display-8", style={'textAlign': 'center'}
        ),        
        # add the actual links
        dbc.Nav(
            [
                dbc.NavLink("Page 1", href="/", active="exact"),
                dbc.NavLink("Page 2", href="/page2_url", active="exact"),
            ],
            vertical=True, # well, that means not horizontally
            pills=True, # adds a blue square around the active selection
            style={"font-size":20, 'textAlign': 'center'}
        ),
    ],
    className="sidebar_style"
)