.slideshow__arrow_l {
    height: 10px;
    width: 10px;
    border-top: 3px solid #000;
    border-right: 3px solid #000;
    transform: translateY(10%) translateX(10%) rotate(45deg);
    border-color: black;
}

.slideshow__arrow_r {
    height: 10px;
    width: 10px;
    border-top: 3px solid #000;
    border-right: 3px solid #000;
    /*transformで矢印の位置や方向をカエル*/
    transform: translateY(10%) translateX(10%) rotate(225deg);
    border-color: black;
}
.slideshow_l {
    height: 50px;
    width: 50px;
    /*position: fixed;*/
    right: 30px;
    bottom: 30px;
    background: #fff;
    border: solid 2px #000;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 2;
}

.slideshow_r {
    height: 50px;
    width: 50px;
    /*position: fixed;*/
    right: 30px;
    bottom: 30px;
    background: #fff;
    border: solid 2px #000;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 2;
}