<table width="100%" height="100%" cellpadding="0" cellspacing="0">
    <tr>
        <td height="100%" valign="middle" align="center">
            <form class="signin_form" action="" method="post">
                <img style="border-radius:10%;margin-bottom: 50px;" src="/i/logo.svg" width="165" height="62" />
                <?php
                echo $form->renderGlobalErrors();
                echo $form->renderHiddenFields();
                echo '<div class="signin_form__field">' . $form['username']->render() . $form['username']->renderError() . '</div>';
                echo '<div class="signin_form__field">' . $form['password']->render() . $form['password']->renderError() . '</div>';
                ?>
                <button class="btn_out btn">Войти</button>
            </form>
        </td>
    </tr>
</table>