<input type="hidden" name="project_name" value="3wit.ru">
<input type="hidden" name="admin_email" value="lianaza@mail.ru">
<input type="hidden" name="form_subject" value="Заявка на кровать">

function adopt($text) {
return '=?UTF-8?B?'.Base64_encode($text).'?=';
}

$headers = "MIME-Version: 1.0" . PHP_EOL .
"Content-Type: text/html; charset=utf-8" . PHP_EOL .
'From: '.adopt($project_name).' <lianaza@mail.ru>' . PHP_EOL .
'Reply-To: lianaza@mail.ru' . PHP_EOL;

mail($admin_email, adopt($form_subject), $message, $headers );