原文章链接：[圆锥渐变](http://mp.weixin.qq.com/s?__biz=MzAxODE2MjM1MA==&mid=2651552310&idx=3&sn=04fe16c2868d8c9ef4cbfbae2d926626&chksm=8025adf7b75224e1cea545732fd1670ef571f147a771891cd15d23ec36b48d11b7f48e0e9b23&mpshare=1&scene=23&srcid=0704OrrBBOE4R2c9X5U4zn3Y#rd) leaverou提供的案例：[leaverou](https://leaverou.github.io/conic-gradient/) 自己编写的demo：[conicGradient](http://show.funlee.cn/page/conicGradient.html)