Text color of gr.Examples is invisible with gr.themes.Monochrome

[Jason-cs18]

• [x] I have searched to see if a similar issue already exists. I want to show examples within gr.themes.Monochrome(). I have checked out the theme document, but I cannot find any helpful information.

with gr.Blocks(title="Audio Generation", theme=gr.themes.Monochrome()) as demo:
    gr.Markdown(description_tts)
    input = gr.Textbox(label="需要转换的文本", value="最近很辛苦，五一我要出去找个地方散散心！")
    voice_style = gr.Dropdown(["男声1-台湾话", "男声2-香港话", "男声3-普通话", "男声4-普通话", "男声5-普通话", "男声6-普通话", "女声1-普通话", "女声2-普通话", "女声3-辽宁话", "女声4-山西话", "女声5-香港话", "女声6-香港话", "女声7-台湾话", "女声8-台湾话"], label="默认角色", value="女声7-台湾话")
    # custom_audio = gr.Audio(label="自定义声音", type='filepath')
    output = gr.Audio(label="合成的语音")
    submit_button = gr.Button("提交")
    # clear_button = gr.ClearButton("清空"),
    submit_button.click(
        fn=audio_generation,
        inputs=[input, voice_style],
        outputs=output
    )
    gr.Examples(
        examples=audio_examples,
        inputs=[input, voice_style],
        label="案例",
    )

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