#title {
    text-align: center;
}
#header {
    padding: 10vh 0px 20px;
}
#centered-table {
    margin: auto;
    border-collapse: collapse;
}
th, td {
    padding: 6px 18px;  /* top_bottom_pad left_right_pad */
    text-align: center;
}
a:visited, a:link {
    color: blue;
}