如何在Altair堆叠条形图工具提示中显示标准化类别

import altair as alt
import pandas as pd

data = pd.DataFrame({
    'category': ['A', 'B', 'C'],
    'value1': [10, 20, 30],
    'value2': [20, 30, 40],
    'value3': [15, 25, 35]
})

data_normalized = data.set_index('category').apply(lambda x: x / x.sum(), axis=1).reset_index()

chart = alt.Chart(data_normalized).mark_bar().encode(
    x='category',
    y='value1',
    color=alt.Color('value1', scale=alt.Scale(scheme='viridis')),
    tooltip=['category', 'value1']
).properties(
    width=400,
    height=300
)

chart.show()