iframe {
    border: 0;
    width: 95%;
    height: 800px;
}

.material_table{
    margin: 0 auto;
    text-align: center;
    width: 50%;
    min-width: 820px;
    border-collapse: collapse
}

.material_table tr,.material_table td{
    border: 1px solid black;
}