title: The purpose of 100 percent width for body
body: <p>What is the possible purpose of <code>width: 100%</code> for body and html elements?</p>
  
  <p>Sometimes I could see something like this reset-like snippet on live websites, as well at StackOverflow answers:</p>
  
  <pre><code>html, body
  {
    width:  100%; /* ? */
    height: 100%;
    margin: 0;
  }
  </code></pre>
  
  <p>The question may sound silly, but it really bother me. I don't like the situation in which I have some "black magic" in the root elements of HTML-document. This makes me feel that I don't understand the fundamental outlines of what I'm doing.</p>