Color table

            <?php
                echo '<table border="1" cellpadding="2">';
                $kleuren = array('00','33','66','99','cc','ff');

                for ($red = 0; $red < 6; $red++) {

                    for ($green = 0; $green < 6; $green++) {
                        echo '<tr>';

                        for ($blue = 0; $blue < 6; $blue++) {
                            $color = $kleuren[$red].$kleuren[$green].$kleuren[$blue];
                            $colorinv = $kleuren[5-$red].$kleuren[5-$green].$kleuren[5-$blue];


                            if ($kleuren[$red] == "ff" && $kleuren[$green] == "ff" && $kleuren[$blue] == "ff") {
                                echo '<th' . ' style="background-color:#' . $color  . ';' . 'color:black;' . '">' . '#' . $color .'</th>';
                            }

                            else {
                                echo '<th' . ' style="background-color:#' . $color . ';' . $colorinv . ';">' . '#' . $color . '</th>';
                            }
                        }
                        echo '</tr>';
                    }
                }

        echo '</table>';
?>