script.js

var character = document.querySelector(".character");
var block = document.querySelector(".block");

function jump() {
    if (character.classList != "animate") {
        character.classList.add("animate");
    }
    setTimeout(function() {
        character.classList.remove("animate");
    }, 500);
}

var checkDead = setInterval(function() {
        var characterTop =
            parseInt(window.getComputedStyle(character).getPropertyValue("top"));
        var blockLeft =
            parseInt(window.getComputedStyle(block).getPropertyValue("left"));
        if (blockLeft < 20 && blockLeft > 0 && characterTop >= 130) {
            block.style.animation = "none";
            block.style.display = "none";
            alert("You are not the greatest man that ever lived :( refresh page to play again");
        }
    },
    10);