https://compuclass.com.br/texto.asp?ID=117
http://www.w3c.br/divulgacao/guiasreferencia/css2/
https://developer.mozilla.org/pt-BR/docs/Web/CSS/CSS_Reference
Notice: file_get_contents(): Read of 8192 bytes failed with errno=21 Is a directory in /var/www/vhosts/rolfjdietz.de/httpdocs/data/uploads/scripts/csseditor.php on line 36