style.css

html {
    background-color: black !important;
}
body {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    height: 100vh;
    width: 100vw;
    margin: 0;
    overflow: hidden;
    text-align: center;
    background-color: black !important;
    /* background-image: url("bakcground.png"); */

    min-height: 100vh;
    overflow: auto;

    min-height: 100vh;
}

#visualiser {
    margin-top: 300px;
    cursor: pointer;
    position: relative;
    background-image: url("slika.jpg");
    background-position: center;
    text-align: center;
    background-size: 50% 100%;
    background-position: center;
    background-repeat: no-repeat;
}

/* #visualiser:nth-child(1) {
    filter: url(#transmissionerror);
}
#visualiser:nth-child(2) {
    filter: grayscale(100%) contrast(1000%);
    mix-blend-mode: multiply;
} */

.datum {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
}

#text {
    font-size: 30px;
    color: #ffffff;
    font-family: "Inter", sans-serif;
    font-style: bold;
    font-weight: 800;
}

.opis {
    margin-bottom: 120px;
    width: 50%;
}

#textopis {
    font-family: "Inter", sans-serif;
    color: #ffffff;
    text-align: left;
}

@media screen and (max-width: 768px) {
    #textopis {
        font-size: 12px;
    }

    .opis {
        width: 95%;
    }
    .datum {
        top: 50%;
    }
    #text {
        font-size: 20px;
    }
    #visualiser {
        background-size: 100vh;
        justify-content: center;
        align-items: center;
    }
}