<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>CSS calc() Example</title>
  <style>
    /* Fixed header style */
    header {
      background-color: #3498db;
      color: white;
      height: 50px;
      text-align: center;
      line-height: 50px; /* Center the text vertically */
    }

/* Section style that takes full height minus the header height */
    section {
      background-color: #2ecc71;
      height: calc(100vh - 50px); /* Full height minus header height */
      padding: 20px;
      color: white;
    }

/* Simple content style */
    h2 {
      font-size: 24px;
      text-align: center;
    }
  </style>
</head>
<body>

<header>
    My Header
  </header>

<section>
    <h2>Content that takes full screen height minus the header</h2>
    <p>This section uses the CSS calc() function to adjust its height based on the viewport height, accounting for the fixed header.</p>
  </section>

</body>
</html>