Design a massive circular futuristi...

Design a massive circular futuristic sky-city hub, fitting exactly within a 250x250 block square footprint, height unrestricted. The layout uses strict 8-fold radial symmetry, like a spoked wheel seen from above, centered on a single vertical axis. At the very center stands one extremely tall, slender spire tower, roughly 30 blocks wide at its base, tapering upward through several setback tiers. Build it from white quartz block and smooth quartz with polished light gray concrete trim. Cover the tower's vertical facade with tall glowing cyan-blue stained glass window strips running floor to floor, separated by thin quartz pillar mullions. Cap the tower with a stepped pyramid crown made of quartz stairs, then a thin antenna mast built from iron bars and a lightning rod at the very