#gallerybox {
    position: fixed;
    left: 0;
    top: 0;
    width: 100vw;
    height: 100vh;
}

#gallerybox>span {
    display: none;
    position: absolute;
    right: 10%;
    top: 10%;
    padding: 1em;
    z-index: 1;
    font-family: Helvetica, Verdana, Arial, sans-serif;
    font-size: 12px;
    color: #ccc;
    cursor: pointer;
}

#gb-overlay {
    position: absolute;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
}

#gb-big {
    position: absolute;
}

#gb-list {
    position: absolute;
    width: 100%;
    height: 150px;
    box-sizing: border-box;
    left: 0;
    bottom: 0;
    padding: 0 20px;
    text-align: center;
    white-space: nowrap;
    overflow-x: hidden;
}

#gb-list:before {
    content: '';
    display: inline-block;
    vertical-align: middle;
    height: 100%;
}

#gb-list>.left,
#gb-list>.right {
    position: fixed;
    width: 20px;
    height: 150px;
    bottom: 0;
    line-height: 150px;
    font-family: Helvetica, Verdana, Arial, sans-serif;
    font-weight: 600;
    color: #ccc;
    background-color: rgba(51, 51, 51, 0.75);
    cursor: pointer;
}

#gb-list>.left {
    left: 0;
    border-radius: 0 100% 100% 0 / 0 50% 50% 0;
}

#gb-list>.right {
    right: 0;
    border-radius: 100% 0 0 100% / 50% 0 0 50%;
}

#gb-list>img {
    vertical-align: middle;
    margin: 0 1em;
    max-height: 75%;
    cursor: pointer;
}