#divIntro {
    display: grid;
    grid-column-gap: 10px;
    grid-template-columns: 2.8fr 1fr;
    width: 92%;
}

#tableMassTotal {
    border-collapse: collapse;
    margin-left: auto;
    margin-right: auto;
    margin-top: 10px;
    width: 75%;
}

    #tableMassTotal tr:last-child td {
        border-top-color: black;
        border-top-style: solid;
        border-top-width: 2px;
    }

    #tableMassTotal th {
        background-color: rgb(247, 247, 247);
        border-color: rgb(150, 150, 150);
        border-style: solid;
        border-width: 1px;
        padding: 8px;
        text-align: center;
    }

        #tableMassTotal th:nth-child(1) {
            text-align: left;
        }

    #tableMassTotal td {
        border-color: rgb(170, 170, 170);
        border-style: solid;
        border-width: 1px;
        padding: 8px;
        text-align: center;
    }

    #tableMassTotal td:nth-child(1) {
        text-align: left;
    }

#tableWtFrac {
    border-collapse: collapse;
    margin-left: auto;
    margin-right: auto;
    margin-top: 10px;
    width: 65%;
}

    #tableWtFrac th {
        background-color: rgb(247, 247, 247);
        border-color: rgb(150, 150, 150);
        border-style: solid;
        border-width: 1px;
        padding: 8px;
        text-align: center;
    }

        #tableWtFrac th:nth-child(1) {
            text-align: left;
        }

    #tableWtFrac td {
        border-color: rgb(170, 170, 170);
        border-style: solid;
        border-width: 1px;
        padding: 8px;
        text-align: center;
    }

        #tableWtFrac td:nth-child(1) {
            text-align: left;
        }