script1.js

var dino = document.querySelector(".dino");
var gameOver = document.querySelector(".gameOver");
var obstacle = document.querySelector(".obstacle");
var playGame = document.getElementById("button");
var newScore = document.getElementById("score");
var playButton = document.getElementById("button2");
var start = document.querySelector(".initial");
var display = document.querySelector(".gameContainer");

score = 0;
cross = true;

playButton.addEventListener("click", run);


game();

function game(){
    document.onkeydown = function (e) {
        if (e.keyCode == 38) {
          dino.classList.add("animateDino");
          setTimeout(() => {
            dino.classList.remove("animateDino");
          }, 700);
        }
      
        if (e.keyCode == 39) {
          dx = parseInt(window.getComputedStyle(dino, null).getPropertyValue("left"));
          dino.style.left = dx + 112 + "px";
        }
      
        if (e.keyCode == 37) {
          dx = parseInt(window.getComputedStyle(dino, null).getPropertyValue("left"));
          dino.style.left = dx - 112 + "px";
        }
      }
}

setInterval(() => {

    dx = parseInt(window.getComputedStyle(dino, null).getPropertyValue("left"));
    dy = parseInt(window.getComputedStyle(dino, null).getPropertyValue("top"));
    ox = parseInt(window.getComputedStyle(obstacle, null).getPropertyValue("left"));
    oy = parseInt(window.getComputedStyle(obstacle, null).getPropertyValue("top"));
    offsetX = Math.abs(dx - ox);
    offsetY = Math.abs(dy - oy);

    if (offsetX < 73 && offsetY < 52) 
    {
        gameOver.innerHTML = "Game Over !!!!";
        obstacle.classList.remove("obstacleAni");
        playGame.style.visibility = "visible";
        playGame.addEventListener("click", );
        obstacle.style.display = "none";
        dino.style.display = "none";
        newScore.innerHTML = "Your Score is  " + (score-1);
        newScore.style.visibility = "visible";
        scoreCont.style.visibility = "hidden";

    }

    else if (offsetX < 145 && cross) {

        score += 1;
        updateScore(score);
        cross = false;
        setTimeout(() => {
          cross = true;
        }, 2000);
        setTimeout(() => {
          aniDur = parseFloat(window.getComputedStyle(obstacle, null).getPropertyValue("animation-duration"));
          if(aniDur >= 5 )
          {
            newDur = aniDur - 0.1;
            obstacle.style.animationDuration = newDur + "s";
            console.log("New animation duration: ", newDur);
          }
        }, 1000);
      }
    
}, 20);

function updateScore(score) {
  scoreCont.innerHTML = "Your Score: " + score;
}

function run() {
  if( start.style.display === "block")
  {
    start.style.display = "none";
    display.style.display = "block";
  }

  else
  {
    start.style.display = "block";
    display.style.display = "none";
  }
  
}

function reset()
{
  score = 0 ;
  
}