Highlight a column incl. header with style in Pivottable

Question

I have a dataframe like this:

import pandas as pd
import numpy as np
from pandas import DataFrame
import matplotlib.pyplot as plt

df3 = pd.DataFrame({
    '2020/01' : ['1', '2', '3', '4', '5', '6', '7'], 
    '2020/02'  : ['8', '9', '10', '11', '12', '13', '14'], 
    '2021/01': ['15', '16', '17', '18','19','20', '21'],
    '2022/01': ['22', '23', '24', '25', '26','27', '28']
})

which looks like this:

What I want to do is highlight a specific column, incl. the header.

I found all sorts of way of styling but not how to inlcude the header.

Maybe something like this: