嵌入到APP中，ios系统调整不了图上字体大小echarts 配置项内容和展示

H5页面作图嵌入到APP里面，在ios里面改变不了字体大小，ios的浏览器里面可以改变，安卓手机也可以改变，不知道问题出在哪

      option = {
    "legend": {
        "bottom": 10,
        "left": "center",
        "itemWidth": 12,
        "itemHeight": 12,
        "itemGap": 25,
        "icon": "stack",
        "data": ["未完成", "已完成"],
        "textStyle": {
            "fontSize": 10,
            "fontFamily": "PingFangSC-Regular"
        }
    },
    "series": [{
        "type": "pie",
        "hoverAnimation": false,
        "radius": "70%",
        "center": ["50%", "38%"],
        "label": {
            "normal": {
                "position": "inner",
                "formatter": "{d}%",
                "fontSize": 6
            }
        },
        "data": [{
            "value": 20,
            "name": "未完成"
        }, {
            "value": 64,
            "name": "已完成"
        }]
    }],
    "color": ["#F5A623", "#5B9CD6"]
}