pub const ANIMATION_PROPERTIES_CSS: &str = r#"@property --xui-a-opacity{syntax:"<number>";inherits:false;initial-value:1}@property --xui-band{syntax:"<number>";inherits:true;initial-value:1}"#;Expand description
The custom properties the keyframes animate, registered so they
interpolate (--xui-a-opacity, the opacity factor; --xui-band, the
shimmer band). A CSS renderer adds this ONCE per document.