.js-scroll {
    opacity: 0;
    transition: opacity 500ms;
}

.js-scroll.scrolled {
    opacity: 1;
}

.scrolled.slide-left {
    animation: slide-in-left .5s ease-in-out both;
}

.scrolled.slide-right {
    animation: slide-in-right .5s ease-in-out both;
}

@keyframes slide-in-left {
    0% {
        -webkit-transform: translateX(-200px);
        transform: translateX(-200px);
        opacity: 0;
    }
    100% {
        -webkit-transform: translateX(0);
        transform: translateX(0);
        opacity: 1;
    }
}

@keyframes slide-in-right {
    0% {
        -webkit-transform: translateX(200px);
        transform: translateX(200px);
        opacity: 0;
    }
    100% {
        -webkit-transform: translateX(0);
        transform: translateX(0);
        opacity: 1;
    }
}

@keyframes fade-in-bottom {
    0% {
        -webkit-transform: translateY(50px);
        transform: translateY(50px);
        opacity: 0;
    }
    100% {
        -webkit-transform: translateY(0);
        transform: translateY(0);
        opacity: 1;
    }
}