app/views/_layouts/site.tpl
<?php $this->layout('layout::base') ?>
<?php $this->start('page-content') ?>
<div class="container"><?= $this->section('content') ?></div>
<?php $this->stop() ?>
<?php $this->start('page-scripts') ?>
<script src="<?= base_url('assets/scripts/main.js') ?>"></script>
<?php $this->stop() ?>