Convert Pollen CSS to Bricks JSON

pollen.php

<?php

$css = file_get_contents(dirname(__FILE__) . '/pollen.css');
$css = preg_replace(
    [
        "/\/\*\*[^\/]*\//m", // Remove any comments
        "/\:root\s*\{/", // Remove :root {
        "/\}/", // Remove trailing }
        "/\n\s*\n/m", // Remove any empty lines
        "/^\s*/m", // remove empty spaces from the front end of variables
        "/\:\s*[^\n]+/m" // Remove the value part of the variables (: value)
    ], 
    '', 
    $css
);
$css = array_map(
    function($variable) {
        $variable = str_replace("--", '', $variable);
        $variable_parts = explode('-', $variable);
        $category = array_shift($variable_parts);

        return [
            'category' => $category,
            'variable' => $variable
        ];
    },
    explode("\n", $css)
);

$output_array = [];
foreach($css as $entry) {
    $output_array[$entry['category']][] = $entry['variable'];
}

file_put_contents(dirname(__FILE__) . '/pollen.json', json_encode($output_array, JSON_PRETTY_PRINT));