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                <div id="app"/>


                @import url('');

html {
  display: flex;
  align-items: center;
  justify-content: center;
  height: 100%;

body {
  font-size: 60px;
  font-weight: 700;
  font-family: 'Roboto Mono', monospace;
  color: #5D9199;
  background-color: #A3E3ED;


                const useAnimationFrame = callback => {
  // Use useRef for mutable variables that we want to persist
  // without triggering a re-render on their change
  const requestRef = React.useRef();
  const previousTimeRef = React.useRef();
  const animate = time => {
    if (previousTimeRef.current != undefined) {
      const deltaTime = time - previousTimeRef.current;
    previousTimeRef.current = time;
    requestRef.current = requestAnimationFrame(animate);
  React.useEffect(() => {
    requestRef.current = requestAnimationFrame(animate);
    return () => cancelAnimationFrame(requestRef.current);
  }, []); // Make sure the effect runs only once

const Counter = () => {
  const [count, setCount] = React.useState(0)
  useAnimationFrame(deltaTime => {
    // Pass on a function to the setter of the state
    // to make sure we always have the latest state
    setCount(prevCount => (prevCount + deltaTime * 0.01) % 100)
  return <div>{Math.round(count)}</div>

ReactDOM.render(<Counter />, document.getElementById('app'))