Edit in JSFiddle

let tagsArr = document.querySelectorAll('*');
for (let i = 0; i < tagsArr.length; i++) {
  tagsArr[i].addEventListener("click", e => alert(`Capturing: ${tagsArr[i].tagName}`), true);
}

<section class="main">This is Main Section
  <article class="contnt">
    This is Article 
    <div id="outer">This is outer div</div>
  </article>
</section>

body * {
    margin: 10px;
    border: 1px solid blue;
  }