<iframe width="560" height="315" src="https://www.youtube.com/embed/J6_7phQFlEc" title="YouTube video player" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>
저 빨간부분만 다시 Ctrl + C
그리고 여기 빨간구간에 다시 붙여넣기
<div class="mov"><iframe src="https://www.youtube.com/embed/J6_7phQFlEc" frameborder="0" allowfullscreen=""></iframe></div>