I was bored...

randomgame.js

import { useLayoutEffect, useState } from 'react'

const SECONDS = 0.6

export default function Game() {
  const [x, setX] = useState(0)
  const [y, setY] = useState(0)
  const [score, setScore] = useState(0)

  // Change coordinates every N seconds
  useLayoutEffect(() => {
    const timer = setInterval(() => {
      setX(Math.floor(Math.random() * 500))
      setY(Math.floor(Math.random() * 500))
    }, SECONDS * 1000)

    return () => {
      clearInterval(timer)
    }
  }, [])

  return (
    <>
      <div style={{ textAlign: 'center' }}>
        <h1>{score} points</h1>
      </div>
      <div
        id="root"
        style={{
          height: '100vh',
          width: '100vw',
          backgroundColor: '#000',
        }}
      >
        <div
          style={{
            position: 'absolute',
            height: 40,
            width: 40,
            backgroundColor: 'red',
            left: x,
            top: y,
          }}
          onClick={() => setScore(score + 1)}
        ></div>
      </div>
    </>
  )
}