Implementing Scrollable Images

I was implemented it for images, which shows lists of images inside a container like pdf viewer..I just overide the css property of bloc gallery class, and adding an additional class…

.image-list{
    position: relative !important;
    padding-bottom: 140% !important;
    overflow: hidden !important;
    border: 1px solid #ddd !important;
}
.blocks-gallery-grid{
    position: absolute;
    left: 0;
    top: 0;
    width: 100%;
    bottom: 0;
    right: 0;
    overflow: hidden;
    overflow-y: scroll;
}
.blocks-gallery-grid::-webkit-scrollbar{
    width: 10px;
}
.blocks-gallery-grid::-webkit-scrollbar-thumb {
    background: #888;
    background-image: initial;
    background-position-x: initial;
    background-position-y: initial;
    background-size: initial;
    background-repeat-x: initial;
    background-repeat-y: initial;
    background-attachment: initial;
    background-origin: initial;
    background-clip: initial;
    background-color: rgb(224, 224, 224);
}