Overlay. Colored columns behind the candles are the live order-book depth ratio in the 1–2.5 / 2.5–5 / 5–10% bands around price. Spot green (bids dominant) / red (asks dominant); Futures yellow (bids) / blue (asks). Brighter = stronger imbalance. The three panels plot each band's bid vs ask (toggle OBD ↔ RATIO, RAW ↔ CUM). The combined indicator plots log₂ ratio. Top 10 marks the biggest resting levels. Drag to pan, scroll to zoom, drag the price axis to rescale. Live data needs a real browser tab.