遇到彩虹吃定彩虹

<style type="text/css">
div{
                margin: 0;
                padding: 0;
                width: 500px;
                height: 500px;
                border-radius: 50%;
                box-shadow: 
                0 0 0 5px inset red,
                0 0 0 10px inset orange,
                0 0 0 15px inset yellow,
                0 0 0 20px inset lime,
                0 0 0 25px inset aqua,
                0 0 0 30px inset blue,
                0 0 0 35px inset magenta;
                clip-path: polygon(0 0,100% 0,100% 50%,0 50%);
                
            }
</style>

效果

image.png