Starts about line 1511 in index.css. Issue is the spaceing between .letterspacing and the '{'.
Currently is...
/* Basic cells. */
.table_grid td, .letterspacing{
padding: 5px 8px;
border-bottom: 1px solid #ccc;
}
Should be...
/* Basic cells. */
.table_grid td, .letterspacing {
padding: 5px 8px;
border-bottom: 1px solid #ccc;
}