.BodyContainer {
    display: grid;
    grid-template-rows: auto 1fr;
}

.MainContainer {
    display: grid;
    height: 100%;
    grid-template-rows: 1fr;
    overflow: hidden;  /* 全体のスクロールを防ぐ */

    .NavContainer {
        /* height: 100%; */
        background-color: #f4f4f4;
        overflow-y: auto;
        /* border-right: 1px solid #ddd; */
    }
    
    .MainContentContainer {
        /* height: 100%; */
        padding: 20px;
        background-color: #fff;
        overflow-y: auto;
    }
}