cssutil: command not found

Maybe Your $PATH variable doesn't contain the default paths? echo $PATH should give something like:

[root@server ~]# echo $PATH
/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin

If it's empty, You may set the PATH variable with this command

export PATH="/usr/local/sbin:/usr/local/bin:/sbin:/bin:/usr/sbin:/usr/bin:/root/bin"

On CentOS possible default full paths are:

/usr/bin/cssutil - from package: crm114

You may install the required package with command yum install {package}

On Debian possible default full paths are:

/usr/bin/cssutil - from package: crm114

You may install the required package with command apt-get install {package}

Error in other languages:
cssutil: bevel nie gevind nie
cssutil: comandă negăsită
cssutil: comando não encontrado
cssutil: commande introuvable
cssutil: command not found
cssutil: käsku ei ole
cssutil: không tìm thấy lệnh
cssutil: komanda nerasta
cssutil: Kommando nicht gefunden.
cssutil: kommandot finns inte
cssutil: komut yok
cssutil: nie znaleziono polecenia
cssutil: níor aimsíodh an t-ordú
cssutil: no se encontró la orden
cssutil: no s'ha trobat l'ordre
cssutil: opdracht niet gevonden
cssutil: parancs nem található
cssutil: perintah tidak ditemukan
cssutil: príkaz nenájdený
cssutil: příkaz nenalezen
cssutil: команда не найдена
cssutil: командата не е открита
cssutil: 命令找不到
cssutil: コマンドが見つかりません