.table_yuyama {
    display: block;
    overflow-y: scroll;
    height: calc(100vh/2);
    border:1px solid;
    border-collapse: collapse;
}
.table_yuyama thead th {
    position: sticky;
    top: 0;
    z-index: 1;
    background: white;
    border-top:#FFFFFF;
}