rxs: Reactive CSS

Super fast dynamic CSS rules. Tiny and Dependency-free!

Getting Started

npm install rxs --save

Example Demo

Clone this repo, and open up:

• example/index.html (Move your mouse around + resize window)
• example/hero.html (Scroll)

Quick Example

For this example, we want the height of any element with the class of .fun-height to be exactly 65% of the window's height, in px. It should also update everytime the browser is resized.

<div class="card fun-height">
  ...
</div>

<!-- Add the reactive-css script -->
<script src="../js/rxs.min.js"></script>

In our Javascript, we'll define the Reactive CSS rule. We can set/update the rule by using the .set() method everytime the window is resized.

// Add a new CSS rule to the Reactive Stylesheet
var funHeightCSS = rxs('.fun-height');

window.addEventListener('resize', function() {
  // Everytime the window is resized, update the height property for
  // the class `.fun-height` to a computed height
  funHeightCSS.set({
    height: (window.innerHeight * 0.65) + 'px',
  });
});

Alternatively, you can write the above in a slightly shorter way by passing the style properties as a second argument for rxs():

window.addEventListener('resize', function() {
  // Everytime the window is resized, update the height property for
  // the class `.fun-height` to a computed height
  rxs('.fun-height', {
    height: (window.innerHeight * 0.65) + 'px',
  });
});