AnimationFillStyle
An enumeration over all possible fill-mode values.
Backwards = 2
The animation will apply the values defined in the
first relevant keyframe as soon as it is applied to
the target, and retain this during the delayed period.
The first relevant keyframe depends of the value of
the direction.
Both = 3
The animation will follow the rules for both forwards
and backwards, thus extending the animation properties
in both directions.
Forwards = 1
The target will retain the computed values set by
the last keyframe encountered during execution. The
last keyframe encountered depends on the direction
and the number of iterations.
None = 0
The animation will not apply any styles to the
target before or after it is executing.