.outer-container {
    position: relative;
    width: 1200px;
    overflow: hidden;
}

.group-container {
    display: inline-block;
    text-align: center;
    list-style: none;
    width: 1200px;
    float: left;
}

.group-item {
    display: inline-block;
    background-color: #fff;
    border-radius: 3px;
    box-shadow: 0 0 20px 0 rgba(0,0,0,0.1);
    margin: 10px;
    padding: 20px;
    text-align: center;
    color: #000;
    width: 380px;
}

.left {
    cursor: pointer;
    position: relative;
    top: 200px;
    left: -572px;
    background: rgba(0,0,0,.3);
    z-index: 101;
    line-height: 100%;
    padding: .3125rem;
    font-size: 1.25rem;
    color: #fff;
}

.right {
    cursor: pointer;
    position: relative;
    top: 200px;
    right: -573px;
    background: rgba(0,0,0,.3);
    z-index: 101;
    line-height: 100%;
    padding: .3125rem;
    font-size: 1.25rem;
    color: #fff;
}