请教如何动态修改中间部分的背景颜色echarts 饼配置项内容和展示

鼠标移动之后，中线区域显示鼠标对应的区域的背景色，，如何动态修改这个背景色

      option = {
    color: ['#22c5eb', '#5fefe4', '#9de7b7', '#ff9f7b', '#Fd7092', '#E88ED1', '#94BEFF'],
    series: [{
        name: '税前工资去向',
        type: 'pie',
        radius: ['50%', '70%'],
        avoidLabelOverlap: false,
        selectedMode: false,
        markPoint: {
            label: {
                show: true
            }
        },
        label: {
            normal: {
                show: false,
                position: 'center',
                //动态修改？？？？
                backgroundColor: 'red',

                rich: {
                    a: {
                        color: '#000',
                        fontSize: 16,
                        lineHeight: 20,
                        align: 'left',

                    }
                },
                formatter: "{a|{b} \n ¥{c} \n 比例：({d}%)}"
            },
            emphasis: {
                show: true,
                textStyle: {
                    fontSize: '16',
                    // fontWeight: 'bold'
                },

                padding: [10, 10],
                borderRadius: 10,

            }
        },

        data: [{
                value: 10000,
                name: "税后月薪"
            },
            {
                value: 1000,
                name: "养老保险金"
            },
            {
                value: 500,
                name: "医疗保险金"
            },
            {
                value: 300,
                name: "失业保险金"
            },
            {
                value: 600,
                name: "基本住房公积金"
            },
            {
                value: 300,
                name: "补充住房公积金"
            },
            {
                value: 233,
                name: "个人所得税"
            }
        ]
    }]
};



function test(){
    return 'red'
}