body {
    background-color: lightgray;
}

table {
    border-collapse: collapse;
}

th, td {
    border: 1px solid gray;
}

nav td {
    text-align: center;
    background-color: white;
    border-right: 1px solid black;
    border-left: none;
    border-top: none;
    border-bottom: none;
    padding-left: 5px;
    padding-right: 5px;
}

nav tr :last-child {
    border-right: none;
}