def pentagon() {
repeat(5) {
forward(100)
right(72)
}
}
def bkgrnd=cm.linearGradient(60, 120, black, 100, 45, red, false)
def mlight=cm.linearGradient(60, 120, red, 100, 45, black, false)
cleari()
setSpeed(fast)
setPenColor(mlight)
setBackground(mlight)
setFillColor(bkgrnd)
repeat(180) {
pentagon()
right(2)
}