Open-Close Diff with Bollinger Bands (Up to 8σ)

Hôm kia

1. what this code does
This code does the following

Calculates the difference (diff) between the open (opening) and close (closing) prices
The direction and magnitude of the price change for each candle.
Calculate Bollinger bands from ±3σ to ±8σ
Calculated based on moving average (basis) and standard deviation (stdDev)
Calculates the upper and lower limits of the Bollinger Bands and plots the lines at each σ level (3σ to 8σ).
Changes background color when the Bollinger Band is exceeded.
For example, if the diff is between ±3σ and ±4σ, the background is changed in red or blue.
When a value reaches a Bollinger Band outside of the more outer Bollinger Band (e.g., ±8σ), the transparency of the background color changes to visually highlight the anomaly.