style.css

.game{
    width: 600px;
    height: 200px;
    border: 1px solid black;
    margin: auto;
}

#hero{
    width: 50px;
    height: 50px;
    background-image: url(img/hero.png);
    background-size: 50px 50px;
    position: relative;
    top: 150px;
}

.jump{
    animation: jump 0.3s linear;
}

@keyframes jump{
    0% {
        top: 150px;
    }
    30% {
        top: 130px;
    }
    50% {
        top: 80px;
    }
    80% {
        top: 130px;
    }
    100% {
        top: 150px;
    }
}

#cork{
    width: 20px;
    height: 40px;
    position: relative;
    top: 110px;
    left: 560px;
    background-image: url(img/cork.png);
    background-size: 20px 40px;

    animation: block 1s infinite linear;
}

@keyframes block{
    0%{
        left: 560px;
    }
    100%{
        left: -40px;
    }
}