// 自定义关键字
if($_SERVER['SCRIPT_NAME']=="/admin/write-post.php"){
function themeFields(Typecho_Widget_Helper_Layout $layout) {
    $thumb = new Typecho_Widget_Helper_Form_Element_Text('thumb', NULL, NULL, _t('自定义thumb缩略图'), _t('输入图片URL'));
    $layout->addItem($thumb);

    $thumbSyle = new Typecho_Widget_Helper_Form_Element_Select('thumbStyle', array(
        'default'=>'default(跟随外观设置)',
        'small'=>'small(小版式)'
    ),'default', _t('文章头图样式选择'), '该选项可以单独为该篇文章配置头图样式,以便达到首页多种头图样式交叉的效果');
    $layout->addItem($thumbSyle);
}