#!mojo mojo:sky_viewer
<sky>
<style>
square {
  margin: 50px;
  height: 100px;
  width: 100px;
  background-color: green;
}
</style>
<square />
<script>
import "dart:sky";

void main() {
  Element square = document.querySelector('square');
  double timeBase = null;

  void animate(double time) {
    if (timeBase == null)
      timeBase = time;
    double delta = time - timeBase;
    int rotation = (delta / 10).floor();
    square.style.setProperty("transform", 'rotate(${rotation}deg)');
    window.requestAnimationFrame(animate);
  }

  window.requestAnimationFrame(animate);
}
</script>
</sky>