style.css

body {
    margin: 0;
    background-image: linear-gradient(180deg, #FEEAC0 0%, #e0752d 100% );
    overflow-y: hidden;
}

.night {
    height: 82vh;
    width: 70vw;
    margin: 4rem auto;
    background: url(mars.jpg);
    background-size: cover;
    position: relative;
    box-shadow: 1px 2px 60px rgba(0, 0, 0, 0.4);
    overflow-x: hidden;
}

h1 {
    font-family: 'Irish Grover', cursive;
    color: #141414;
    font-size: 35px;
    text-align: center;
}

.cactus img {
    height: 130px;
    display: block;
    position: absolute;
    bottom: 100px;
    right: -100px;
    background-repeat: repeat-x;
    animation: moveRight 7s linear infinite;
}

.cactus1 img {
    height: 130px;
    display: block;
    position: absolute;
    bottom: 100px;
    right: -950px;
    background-repeat: repeat-x;
    animation: moveRight 7s linear infinite;
}

.cactus2 img {
    height: 130px;
    display: block;
    position: absolute;
    bottom: 100px;
    right: -1650px;
    background-repeat: repeat-x;
    animation: moveRight 7s linear infinite;
}

.walle img {
    height: 135px;
    position: absolute;
    bottom: 8%;
    left: 30%;
    animation: upDown 0.9s linear infinite;
}

.eve img{
    height: 135px;
    position: absolute;
    bottom: 8%;
    left: 5%;
    animation: upDown 0.4s linear infinite;
}

@keyframes moveRight {
    100%{transform: translateX(-2950px)};
}

@keyframes upDown {
    100%{
        transform: translateY(-1px);
    }
    50% {
        transform: translateY(2px);
    }
    0% {
        transform: translateY(-1px);
    }
}