css彩虹 .f111 {width: 200px;height: 200px;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%);}