Html::addCssClass('myClass', 'container') ]); ?>
Html::addCssClass(['myClass', 'myOtherClass']) ]); ?>Here, addCssClass is used to add two CSS classes to the HTML tag generated by the tag method. The first parameter specifies an array of CSS classes to be added. In both examples, the Html class from the Yii PHP framework is used, which means these examples are a part of the Yii Helpers library.