css - Animation fill-mode property

The animation-fill-mode CSS property defines how the styles applied by an animation affect the element before and after the animation executes.

animation-fill-mode: none | forwards | backwards | both


`none`	Default. The element does not retain any animation styles before or after it runs.
`forwards`	The element retains the styles defined in the last keyframe (`to` or `100%`) after the animation ends.
`backwards`	The element applies the styles from the first keyframe (`from` or `0%`) during the delay period, before the animation starts.
`both`	Combines `forwards` and `backwards`. The element retains the first keyframe style during delay, and keeps the last keyframe style after the animation ends.