使用css隐藏显示功能

I am working on hide show functionality using JavaScript

but it occurring error on console for onclick function

I am not getting why this error occurring.

PHP CODE

<?php

$page = '0';

$output.='<div id="my_section" style="display:none;">This is my section</div>';

echo $output;

?>

I page-id is grater than 0 need to display block of div my_section

e.g.

$output.='<div id="my_section" if($page>\'0\') { style="display:none;" } else { style="display:block;" }>This is my section</div>';

i am not getting how to add this condition in php please help