title: how to apply css to particular column of gridview columns in yii2
body: <p>I am new to yii2.. how to apply css to column, column heading of yii2 gridview??</p>
  
  <pre><code>&lt;?php 
  
      $gridColumns = [
                       ['class' =&gt; 'yii\grid\SerialColumn'],
                       ['class' =&gt; 'yii\grid\CheckboxColumn'],  
  
                      'name',
                      'company_mail', //change the color of heading
                      'no_employees',
                      'email:email', 
                      .
                      .
                      .];
              echo GridView::widget([
              'dataProvider' =&gt; $dataProvider,
              'filterModel' =&gt; $searchModel,
              'columns' =&gt; $gridColumns,
      ]); 
      ?&gt;
  </code></pre>