eCSStractor 
Extracts CSS from HTML <style>-Tags, (*1)
(Also the lamest wordplay I could possibly come up with...), (*2)
How
Installation
Install via composer, (*3)
composer require spazzmarticus/e-css-tractor, (*4)
Usage
//Your HTML-Document with one or more <style>-Tags
$html = '<html><head><style>p { color: blue; }</style></head>...<style>h1 { background-color: green; }</style></html>';
$eCSStractor = new eCSStractor();
$css = $eCCStractor->extract($html);
header("Content-type: text/css");
echo $css;
p { color: blue; }
h1 { background-color: green; }
Example
Check out the example/ directory. The styles from input.html are extracted in css.php and used in usage.html., (*5)
What not
This doesn't optimize the styles. GIGO ;), (*6)
Why
I built a tool to send newsletters with. The editor for the newsletter-content had to be able to work with multiple templates (each containing unique styles). By extracting the styles from the templates I was able to dynamically change the template for a preview (outside the editor) and the styles in the editor accordingly., (*7)
Before sending the newsletter the styles are written inline by emogrifier so there was no need to change anyting., (*8)
Wallogit.com
