将自定义css类添加到DataFrame的列(或单元格)

def add_css_class(value):
    # 根据条件返回CSS类名
    if value > 0:
        return 'positive'
    elif value < 0:
        return 'negative'
    else:
        return 'zero'

import pandas as pd

data = {'A': [1, -2, 3, 0],
        'B': [-4, 5, -6, 7]}
df = pd.DataFrame(data)

styler = df.style.applymap(add_css_class)

styled_df = styler.render()
print(styled_df)

<table id="T_9e8e8e2e_8e8e8e8e" >
<thead>    <tr>        <th class="blank level0" ></th>        <th class="col_heading level0 col0" >A</th>        <th class="col_heading level0 col1" >B</th>    </tr></thead><tbody>
                <tr>
                        <th id="T_9e8e8e2e_8e8e8e8elevel0_row0" class="row_heading level0 row0" >0</th>
                        <td id="T_9e8e8e2e_8e8e8e8erow0_col0" class="data row0 col0 positive" >1</td>
                        <td id="T_9e8e8e2e_8e8e8e8erow0_col1" class="data row0 col1 negative" >-4</td>
            </tr>
            <tr>
                        <th id="T_9e8e8e2e_8e8e8e8elevel0_row1" class="row_heading level0 row1" >1</th>
                        <td id="T_9e8e8e2e_8e8e8e8erow1_col0" class="data row1 col0 negative" >-2</td>
                        <td id="T_9e8e8e2e_8e8e8e8erow1_col1" class="data row1 col1 positive" >5</td>
            </tr>
            <tr>
                        <th id="T_9e8e8e2e_8e8e8e8elevel0_row2" class="row_heading level0 row2" >2</th>
                        <td id="T_9e8e8e2e_8e8e8e8erow2_col0" class="data row2 col0 positive" >3</td>
                        <td id="T_9e8e8e2e_8e8e8e8erow2_col1" class="data row2 col1 negative" >-6</td>
            </tr>
            <tr>
                        <th id="T_9e8e8e2e_8e8e8e8elevel0_row3" class="row_heading level0 row3" >3</th>
                        <td id="T_9e8e8e2e_8e8e8e8erow3_col0" class="data row3 col0 zero" >0</td>
                        <td id="T_9e8e8e2e_8e8e8e8erow3_col1" class="data row3 col1 positive" >7</td>
            </tr>
    </tbody></table>