style2.css

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

tr {
    width: 100%;

    background-color: brown;
}

body, html {
    height: 100%;
}

table {
    padding-left: 15%;
    height: 100%;
}

.tHeader {
    background-color: blue;
    height: 50px;
}

.tFooter {
    background-color: blue;
    height: 50px;

}

.insideHeader {

    background-color: yellow;
    height: 50px;
}

.content {
    height: 100%;

}

.leftPanel {
    width: 150px;
    height: 100%;
    background-color: yellow;

}

.content_div {
    height: 100%;
    width: 100%;
    display: flex;
    flex-direction: column;
}

.d1, .d2, .d3 {
    text-align: center;
    background-color: white;
    border: solid 1px black;

}

.d1 {

    flex-grow: 1;
}

.d2 {
    flex-grow: 2;
}

.d3 {
    flex-grow: 3;
}

.d1:hover, .d2:hover, .d3:hover, td:hover {
    cursor: pointer;
    background-color: darkred;
}