I have been struggling with how to style highlight pandas rows based on index names. I know how to highlight selected rows but when I have to highlight based on the index, the code is not working.

Setup

df = pd.DataFrame({'key': list('ABCD'), 'value': range(4)})
print(df)key  value
0   A      0
1   B      1
2   C      2
3   D      3

Highlight rows when key has value 'B' or 'D'

# this worksdf.style.apply(lambda x: ['background: lightgreen' if (x.key == 'B' or x.key == 'D')else '' for i in x], axis=1)

Highlight rows based on index names

# This DOES NOT work
df1 = df.set_index('key')
df1.style.apply(lambda x: ['background: lightgreen' if (x.index == 'B' or x.index == 'D')else '' for i in x], axis=1)

How to highlight the rows based on index names?

Change index to name:

df1.style.apply(lambda x: ['background: lightgreen' if (x.name == 'B' or x.name == 'D')else '' for i in x], axis=1)