echarts pie 图表 显示的label 中内容 字体大小自定义

option = {
    tooltip: {
        trigger: 'item',
        formatter: "{a} <br/>{b}: {c} ({d}%)"
    },
    legend: {
        orient: 'vertical',
        x: 'left',
        data:['直达','营销广告','搜索引擎','邮件营销','联盟广告','视频广告','百度','谷歌','必应','其他']
    },
    series: [
        {
            name:'访问来源',
            type:'pie',
            selectedMode: 'single',
            radius: [0, '30%'],

            label: {
                normal: {
                    position: 'inner'
                }
            },
            labelLine: {
                normal: {
                    show: false
                }
            },
            data:[
                {value:335, name:'直达', selected:true},
                {value:679, name:'营销广告'},
                {value:1548, name:'搜索引擎'}
            ]
        },
        {
            name:'访问来源',
            type:'pie',
            radius: ['40%', '55%'],
            label: {
                normal: {
                    formatter: '{a|{a}}{abg|}
{hr|}
  {b|{b}：}{c}  {per|{d}%}  ',  //label 的内容
                    backgroundColor: '#eee',
                    borderColor: '#aaa',
                    borderWidth: 1,
                    rich: {//定义不同地方的文字的字体大小和颜色
                        a: {
                            color: '#999',
                            lineHeight: 22,
                            align: 'center'
                        },
                        hr: {
                            borderColor: '#aaa',
                             '100%',
                            borderWidth: 0.5,
                            height: 0
                        },
                        b: {
                            fontSize: 16,
                            lineHeight: 33
                        },
                        per: {
                            color: '#eee',
                            backgroundColor: '#334455',
                            padding: [2, 4],
                            borderRadius: 2
                        }
                    }
                }
            },
            data:[
                {value:335, name:'直达'},
                {value:310, name:'邮件营销'},
                {value:234, name:'联盟广告'},
                {value:135, name:'视频广告'},
                {value:1048, name:'百度'},
                {value:251, name:'谷歌'},
                {value:147, name:'必应'},
                {value:102, name:'其他'}
            ]
        }
    ]
};

这是借助官网上的列子。