style.css

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

.splash_wrap {
    width: 100%;
    height: 500vh;
    background: #000;
    font-family: "PP Neue Montreal";
}

.lottie-container .animation {
    position: fixed;
    width: 100vw;
    height: 100vh;
    top: 0;
    z-index: -1;
    filter: saturate(2);
}

.animation:after {
    content: "";
    background-image: url("https://upload.wikimedia.org/wikipedia/commons/7/76/1k_Dissolve_Noise_Texture.png");
    height: 200%;
    width: 200%;
    position: fixed;
    top: 0;
    left: 0;
    opacity: 0.1;
    animation: animateGrain 8s steps(10) infinite;
}

.gradient {
    width: 100vw;
    position: relative;
    height: 200vh;
    background: linear-gradient(180deg,
            rgba(0, 0, 0, 0) 0%,
            rgba(0, 0, 0, 1) 100%);
    z-index: 1;
}

.website-content {
    position: relative;
    width: 100%;
    height: 300vh;
    padding: 2em;
    background: #000;
    color: #fff;
    z-index: 1;
}

.end-lottie {
    position: absolute;
    top: 100vh;
    width: 100%;
    height: 1px;
}

@keyframes animateGrain {

    0%,
    100% {
        transform: translate(0, 0);
    }

    10% {
        transform: translate(-5%, -10%);
    }

    20% {
        transform: translate(-15%, -20%);
    }

    30% {
        transform: translate(-5%, -10%);
    }

    40% {
        transform: translate(-15%, -20%);
    }

    50% {
        transform: translate(-5%, -10%);
    }

    60% {
        transform: translate(-15%, -20%);
    }

    70% {
        transform: translate(-5%, -10%);
    }

    80% {
        transform: translate(-15%, -20%);
    }

    90% {
        transform: translate(-5%, -10%);
    }

    100% {
        transform: translate(-15%, -20%);
    }
}