边框颜色设置echarts 柱状配置项内容和展示

边框颜色设置时怎么按需设置

      option = {
    title: {
        text: 'Awesome Chart'
    },
    xAxis: {
        data: ['Sun', 'Mon', 'Tue', 'Wed', 'Thu', 'Fri', 'Sat']
    },
    yAxis: {},
    series: [{
        type: 'bar',
        barWidth: '60%',
        data: [10, 52, -200, 334, 390, -330, 220],
        itemStyle: {
            normal: {
                color: function(params) {
                    if (params.data > 0) {
                        return '#1f2227'
                    } else {
                        return '#DC2625'
                    }
                },
                borderColor: function(params) {
                    if (params.data > 0) {
                        return '#0CF601'
                    } else {
                        return '#DC2625'
                    }
                },
                borderWidth: 2
            }
        }
    }]
};