search.html

<!DOCTYPE html>
<html>
<head>
    <link rel="stylesheet" type="text/css" href="styles.css">
</head>
<body>
    <div id="header-container">
        <!-- The header will be inserted here -->
    </div>

    <div id="main-content">
        <div id="left-panel" style="width: 100%;">
            <!-- Content for the left panel goes here -->
            Search
        </div>

        <div id="right-panel">
            <!-- Content for the right panel goes here -->
        </div>
    </div>

    <div id="footer">
        <!-- Additional information goes here -->
    </div>

    <!-- Add the script to insert the header -->
    <script>
        fetch('header.html')
            .then(response => response.text())
            .then(data => {
                document.getElementById('header-container').innerHTML = data;
            });
    </script>
</body>
</html>