cellOptions

pub fn cellOptions(self: *const Borders, cell: Cell) CellOptions {
        var border = self.internal;
        if (cell.col_num == 0)
            border.x = self.external.x;
        if (cell.row_num == 0)
            border.y = self.external.y;
        if (cell.row_num == self.num_rows - 1)
            border.h = self.external.h;
        if (cell.col_num == self.num_cols - 1)
            border.w = self.external.w;
        return self.cell_opts.override(.{ .border = border, .background = true });
    }