t" content="The top margin of an in-flow block-level element is adjoining to its first in-flow block-level child's top margin if the element has no top border, no top padding, and the child has no clearance." />

  <style type="text/css"><![CDATA[
  body
  {
  background-color: white;
  margin: 8px;
  }

  div#parent-block-container
  {
  background-color: red;
  margin: 0px;
  width: 100%;
  }

  div#child-block
  {
  background-color: green;
  color: white;
  margin: 100px 0px;
  }
  ]]></style>

 </head>