<!DOCTYPE html>
<!--
 | For nested inline non-replaced elements,
 |   https://www.w3.org/TR/CSS21/visudet.html#line-height
 -->
<html>
<head>
  <style>
    body {
      margin: 0px;
      font-family: Roboto;
      font-size: 16px;
    }
  </style>
</head>
<body>
<div style="width:150px; background-color:#FFF9C4;">
  x
  <span style="background-color:#FDD835">
    x
    <span style="border:5px; border-style:solid; padding: 10px; background-color:#F9A825">
      x
      <span style="line-height: 80px; font-size: 50px; background-color: #F57F17;">
        x
      </span>
      x
    </span>
    x
  </span>
  x
</div>
</body>
</html>