title: letter-spacing does not work on mobile browsers only desktop
body: <p>I'm using sizes in "REM" and to my surprise the letter-spacing is not working in mobile browsers, Android and iOS. Desktop Work Fine.</p>
  
  <p>CSS</p>
  
  <pre><code>#header{
   position: relative;
   text-align: center;
   overflow: hidden;
   height: initial;
  }
  
  #header h1{
   position: absolute;
   font-size: 12rem;
   right: 3rem;
   margin: 0;
   text-shadow: 0 4px #570b0b;
   letter-spacing: -0.7rem; /* Work Only Desktop */
  }
  </code></pre>
  
  <p>desktop:
  <img src="https://i.stack.imgur.com/pymOi.jpg" alt="enter image description here"></p>
  
  <p>mobile:
  <img src="https://i.stack.imgur.com/2EBTI.jpg" alt="enter image description here"></p>