#scrollbar {
    height: 420px;
    width: 230px;
}

#scrollbar .up, 
#scrollbar .down {
    width: 100%;
    text-align: center;
    display: block;
    cursor: pointer;
    margin-top: 10px;
}

#scrollbar .down {
    margin-bottom: 10px;
    margin-top: 0;
}

#scrollbar .up img, 
#scrollbar .down img {
    border: none;
}