<!doctype html>
<style>
  #greenrect {
    width: 100%;
    height: 100%;
    border: 1px solid green;
    box-sizing: border-box;
  }
  #outer {
    padding-top: 1.7px;
    width: 300.8px;
    height: 250.1px;
  }
  #outer2 {
    padding-top: 1.4px;
    width: 300.8px;
    height: 250.1px;
  }
</style>
<body>
  <div id="outer">
    <div id="greenrect"></div>
  </div>
  <div id="outer2">
    <div id="greenrect"></div>
  </div>
</body>