title: Body margin-top and header margin-top both margins from the top of the browser
body: <p>Let's say body is set to margin-top:20px and then inside body there's header which is set also to margin-top:20px. So shouldn't technically header margin from the top of the body which is already 20px off from browser top? Because in my situation header margin-top doesn't work at all/or it also simply margins off of the browser top side.</p>
  
  <p>It should be body 20px off and then header 20px off from body (so it should be technically header is off 40px from the top of the browser).</p>