Remove the stroke or fill color of an object
To transform to or from a transparent stroke value or fill value, use the Alpha slide bar on the Color panel to specify the opacity of the stroke or fill. A value of 0 renders the stroke or fill completely transparent. You can animate the value of the Alpha channel. If you want to animate both the stroke value and fill value together, you should animate object visibility or object opacity rather than animating the value of the Alpha channel for each property separately.
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