-sd-animation: sd-fadeIn; –sd-duration: 250ms; –sd-easing: ease-in;

It looks like your message was cut off. Do you want a continuation about implementing an element with data-sd-animate (e.g., implementing an animation attribute), or were you asking about something else? Reply with the rest of the text or pick one:

1. Implementing an HTML attribute data-sd-animate for CSS/JS animations
2. Implementing a data attribute in a framework (React/Vue) to trigger animations
3. Implementing an animation system (attribute-driven) for accessibility and performance

I’ll provide a full example and steps for the option you choose.