max
The maximum vertical pan offset relative to the height of the ReaderView's safe area, as defined in the ReaderView's contentDisplayAreaOptions.
If this option is not specified or set to null, the value from IReaderViewOptions.gestureOptions.panZoom.maxPanOffsetVertical will be used.
Example: Setting it to "0%" will not allow the top of the publication to be panned further down than the top of the safe area (and the opposite for the bottom).
Example: Setting it to "50%" will allow the top of the publication to be panned to the midpoint of the safe area (and the same for the bottom).
Example: Setting it to "100%" will allow the publication to be panned all the way outside the safe area.
Example: Setting it to 80 CSS_PIXELS (or DEVICE_PIXELS) will not allow the top of the publication to be panned further down than 80 CSS_PIXELS (or DEVICE_PIXELS) from the top of the safe area (and the opposite for the bottom).