build(); } } if (!function_exists('random_bgc')) { function random_bgc(?int $idx = null): string { $colors = ['red', 'blue', 'orig', 'green', 'violet', 'purple', 'brown']; $color = is_null($idx) ? $colors[array_rand($colors)] : $colors[$idx % count($colors)]; return "think-bg-{$color}"; } }