Add progress bar to each slick slide

progress-slick.scss

@keyframes scale-x-zero-to-max {
    0% {
        transform: scaleX(0);
    }

    100% {
        transform: scaleX(1);
    }
}

.slick-slide {
    &:after {
        background: blue;

        display: block;
        content: "";

        width: 100%;
        height: .25rem;

        position: absolute;
        left: 0;
        bottom: 0;
        z-index: 99;

        transform: scaleX(0);
        transform-origin: left 50%;
    }

    &.slick-active:after {
        animation: scale-x-zero-to-max 6s linear .8s 1 forwards; // Note that 6s should be same as Slick's autoplaySpeed and .8s same as speed
    }
}