How to zoom 100% in html?

1 
<style>
  html{
  zoom: 100%;
}
  .red-text {
    color: red;
  }

  h2 {
    font-family: Lobster, Monospace;
  }

  p {
    font-size: 16px;
    font-family: Monospace;
  }
  smaller-image{
    width:100px;
  }
</style>

<h2 class="red-text">CatPhotoApp</h2>

<img class="smaller-image" src="https://bit.ly/fcc-relaxing-cat" alt="A cute orange cat lying on its back. ">

<p class="red-text">Kitty ipsum dolor sit amet, shed everywhere shed everywhere stretching attack your ankles chase the red dot, hairball run catnip eat the grass sniff.</p>
<p class="red-text">Purr jump eat the grass rip the couch scratched sunbathe, shed everywhere rip the couch sleep in the sink fluffy fur catnip scratched.</p>
2

From the documentation:

A zoom factor of 1.0 or 100% corresponds to no zooming. Larger values zoom in. Smaller values zoom out.