<div class="container">
<button id="btn" class="btn btn-primary">隱藏選單</button>
<div class="border border-dark mt-3">
<h1 class="border-bottom">標題</h1>
<p>Lorem ipsum dolor sit amet consectetur adipisicing elit. Facilis commodi numquam, sequi illo qui nobis tempore hic voluptatibus assumenda soluta nisi accusantium maiores quos eius. Autem saepe consequuntur repellendus quis!</p>
</div>
</div>
$(document).ready(function(e){
$('#btn').click(function(e){
$('h1').toggle();
$('p').toggle();
})
})