I have made many projects using the dashboard template, if you can add the class generator option in the gii feature with the following example
in Menu Widget :
<?= Menu::widget([
'items' => [
['label' => '<span class="pcoded-micon"><i class="feather icon-home"></i></span>
<span class="pcoded-mtext">Dashboard</span>', 'url' => ['site/index']],
['label' => '<span class="pcoded-micon"><i class="feather icon-help-circle"></i></span>
<span class="pcoded-mtext">About</span>', 'url' => ['site/about']],
[
'label' => '<span class="pcoded-micon"><i class="feather icon-grid"></i></span>
<span class="pcoded-mtext">Master</span>',
'url' => 'javascript:void(0)',
'options'=>['class'=>'pcoded-hasmenu'],
'items' => [
['label' => '<span class="pcoded-mtext">Contact Us</span>', 'url' => ['site/contact']],
],
'itemOptions' => ['class'=>'pcoded-submenu'],
],
['label' => '<span class="pcoded-micon"><i class="feather icon-log-out"></i></span>
<span class="pcoded-mtext">Logout</span>', 'url' => ['site/logout']],
],
'encodeLabels' => false,
'activateParents' => true,
'itemOptions' => [
'class' => '',
],
'options' => [
'class' => 'pcoded-item pcoded-left-item',
],
'linkTemplate' => '
<a href="{url}" class="waves-effect waves-dark">
{label}
</a>',
'submenuTemplate' => '<ul class="pcoded-submenu">{items}</ul>',
]); ?>
in ActiveField
<?= $form->field($model, 'username', [
'options' => ['class' => 'form-group form-primary'],
'inputOptions' => [ 'class' => 'form-control fill'],
'labelOptions' => [ 'class' => 'float-label'],
'template' => '{input}<span class="form-bar"></span>{label}{error}{hint}'
])->textInput(['autofocus' => true,], [ 'class' => 'form-group form-primary',]) ?>
<?= $form->field($model, 'password', [
'options' => ['class' => 'form-group form-primary'],
'inputOptions' => ['class' => 'form-control fill'],
'labelOptions' => [ 'class' => 'float-label'],
'template' => '{input}<span class="form-bar"></span>{label}{error}{hint}'
])->passwordInput(['autofocus' => true,], [ 'class' => 'form-group form-primary',]) ?>
Thank you