What “-sd-animation: sd-fadeIn; –sd-duration: 250ms; –sd-easing: ease-in;” Means and How to Use It
Those three declarations are custom CSS properties and a shorthand custom property likely used by a design system to control a simple fade-in animation. Here’s a concise explanation and a minimal, practical example you can drop into a project.
Breakdown
- -sd-animation: sd-fadeIn;
- Selects a named animation variant from the design system (here, “sd-fadeIn”).
- –sd-duration: 250ms;
- Sets the animation duration to 250 milliseconds.
- –sd-easing: ease-in;
- Sets the timing function to ease-in for a smooth start.
How it typically works
A design system defines keyframes and a rule that reads these custom properties and applies them via the animation shorthand. Components then set the properties to change animation type, duration, and easing without repeating full animation declarations.
Minimal example
CSS (include in your stylesheet):
css
:root {–sd-duration: 250ms; –sd-easing: ease-in; -sd-animation: sd-fadeIn;}
/* Design system animation definitions /@keyframes sd-fadeIn { from { opacity: 0; transform: translateY(6px); } to { opacity: 1; transform: translateY(0); }}
/ A utility that reads the custom property and applies animation */.sd-animated { animation-name: var(-sd-animation); animation-duration: var(–sd-duration, 250ms); animation-timing-function: var(–sd-easing, ease-in); animation-fill-mode: both; will-change: opacity, transform;}HTML usage:
html
<div class=“sd-animated” style=”-sd-animation: sd-fadeIn; –sd-duration: 250ms; –sd-easing: ease-in;”> Fade-in content</div>Tips
- Use sensible fallbacks in the utility (as shown) so missing custom properties don’t break styles.
- For accessibility, avoid animating motion-sensitive users: respect the prefers-reduced-motion media query.
Leave a Reply