/*reset*/
* {
    padding: 0;
    margin: 0;
}

/*css variables*/
:root {
    --thumbnail-width: 20px;
    --thumbnail-height: 3px;
    --shadow: rgba(0, 0, 0, .25);
}

html, body {
    height: 100%;
    position: relative;
}

body {
    background: #000;
}

#sections-wrapper {
    position: relative;
    overflow: hidden;
    height: 100vh;
    background: #000;
}

section {
    height: 90vh;
    font-size: 0;
    text-align: center;
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
}

.hide-bottom {
    transform: translateY(100%);
}

.hide-top {
    transform: translateY(-100%);
}

.segment {
    height: 100%;
    display: inline-block;
    overflow: hidden;
    position: relative;
    box-sizing: border-box;
}

.segment-inner {
    position: absolute;
    top: 0;
    background: no-repeat center center / cover;
    height: 100%;
    width: 100vw;
}

.sections-control {
    text-align: center;
    font-size: 0;
    position: absolute;
    right: 25px;
    bottom: 25px;
    box-sizing: border-box;;
}

.section-thumbnail {
    width: var(--thumbnail-width);
    height: var(--thumbnail-height);
    display: block;
    margin-top: 7px;
    padding: 4px 0;
    position: relative;
    transition: .3s all ease;
    opacity: .5;
    cursor: pointer;
    transform-origin: right top;
}

.section-thumbnail:before {
    content: "";
    position: absolute;
    top: 50%;
    left: -5px;
    right: 0;
    height: 5px;
    top: 50%;
    margin-top: calc(var(--thumbnail-height)/2 * -1);
    background: #fff;
}

.section-thumbnail:hover {
    opacity: 1;
}

.section-thumbnail.active {
    transform: scaleX(3);
    opacity: 1;
}