#letter_item_list{
    position: relative;

    width:96%;
    max-width: 800px;
    margin: 0 auto;
    margin-top: 10px;

    display: grid;
    grid-template-columns: repeat(2, 1fr);

    column-gap: 15px;
    row-gap: 15px;
    padding: 30px;
    box-sizing: border-box;
}

#letter_item_list .letter_item{
    border: 1px solid var(--elem-common-base-color);
    position: relative;

    border-radius: 15px;
    overflow: hidden;
    box-sizing: border-box;
    
    cursor: pointer;
}

#letter_item_list .letter_item img{
    width:100%;
    /* 高さは画像サイズ基準 */
}

@media (max-width: 902px) {
    #letter_item_list{
        padding-left: 40px;
        padding-right: 40px;
        row-gap: 15px;
    }
}