title: Why use percentage value for div's width in CSS?
body: <p>I am reading articles about css. I found out that many of writers suggest to use % value for div's width or height.</p>
  
  <p>I am using pixels all the time.</p>
  
  <p>Why should I use % value for div's width or height instead of pixels?</p>
  
  <p>What are the advantages?</p>