<?php
$this->Admin->section('CSS')
->add('html', array('x' => 2, 'html' => '
    <label for="alc_settings_css_ace">Custom Stylesheet</label>
    <div id="alc_settings_css_ace" style="
        width:100%;
        height:400px;
        line-height: 27px;
        font-size: 14px;">'. $css .'</div>
'))->add('hidden', array(
    'id'    => 'alc_settings_css',
    'name'  => 'alc_settings[css]',
    'value' => $css
));