High/low fill coloring in AnyChart assigns separate fill colors to the high and low portions of a range series. This makes it easy to see which side of the range dominates at any point, highlighting directional shifts in the data.
This sample renders a range spline area chart using daily OHLC-style data from early 2018. The high region is filled in semi-transparent green with a green stroke, while the low region uses semi-transparent red with a red stroke. The Y-scale minimum is set to 150 to keep the visible range focused on the price band where all the action occurs.
See the Color Management documentation for all configuration options.