Bot Framework 如何更改聊天头像？

    设置的背景图片都不起作用，还有placeholder 改如何替换？

    附上官网地址，   https://github.com/Microsoft/BotFramework-WebChat/blob/master/samples/webchat-v3/index.html

已解决

 styleSet.avatar = {
            alignItems: 'center',
            borderRadius: '50%',
            color: 'white',
            backgroundColor:'#3a8dde',
            '&.from-user': {
                background:' url(\'/dist/svg/chartIcon.svg\')',
            },
            '&:not(.from-user)': {
                backgroundImage:'url(\'/dist/svg/robotchat-hover.svg\')'
            },
            display: 'flex',
            height: "50px",
            justifyContent: 'center',
            overflow: 'hidden',
            width: "50px"
        };

https://zhidao.baidu.com/question/1609185859785884387.html