radius={6}The hardest case: a 90° swing inside six pixels, leaving square with the next edge.
radius={999}The tangent turns continuously, so there is no seam where the arc meets the straight run.
radius="squircle"A squircle has no constant-radius arc at all, and the beam still tracks it.
beams={2}Phase offsets along one path, so they stay half a lap apart at any duration.
colorFrom / colorToThe tail fades in from one and the head burns out in the other.
reverse · pauseOnHoverHover to freeze it mid-corner and check the angle.