Yii2网格视图单元格的颜色，比较日期条件

use yii\grid\GridView;

echo GridView::widget([
    'dataProvider' => $dataProvider,
    'columns' => [
        'id',
        'name',
        [
            'attribute' => 'date',
            'format' => 'date',
            'contentOptions' => function ($model, $key, $index, $column) {
                $date = strtotime($model->date);
                $today = strtotime(date('Y-m-d'));
                $diff = $date - $today;

                if ($diff < 0) {
                    return ['style' => 'background-color: #ff0000;']; // 过期日期，红色背景
                } elseif ($diff == 0) {
                    return ['style' => 'background-color: #ffff00;']; // 当天日期，黄色背景
                } else {
                    return ['style' => 'background-color: #00ff00;']; // 未来日期，绿色背景
                }
            },
        ],
    ],
]);