PHP code inside Laravel 5 Blade Template

I have to place some PHP code inside Laravel 5 Blade Template. Like below

@foreach ($farmer->tasks as $task)
    @if ($task->pivot->due_at) < date(now))
        $style = 'alert alert-danger';
    @elseif ($task->pivot->due_at) > date(now))
        $style = 'alert alert-success';
    @else
        $style = '';
    @endif
@endforeach

Which is the actual procedure to place PHP code inside Laravel 5 Blade Template ??