final FObj parent = fobj.effectiveParent(context);
if (parent == null) {
return 0;
}
if (axis == RelativeAxis.BLOCK_PROGRESSION) {
return parent.traitBorderSeparationBpd(context);
}
if (axis == RelativeAxis.INLINE_PROGRESSION) {
return parent.traitBorderSeparationIpd(context);
}
throw Property.unexpectedInitialValueArgument(