header.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Index of</title>
    <meta name="viewport" content="width=device-width, initial-scale=1">
    <link rel="stylesheet" href="/fancyindex_theme/assets/css/font-awesome.min.css">
    <link rel="stylesheet" href="/fancyindex_theme/assets/css/style.css">
    <script>
        window.onload = function() {
            var currentIndex = document.getElementsByTagName("h1")[0].textContent;
            var links = document.getElementsByTagName("tbody")[0].getElementsByTagName("a");
            var parentDirectory = links[0];
            
            // set the page title
            document.title = 'Index of ' + currentIndex;
            
            // change the parent directory icon
            if (parentDirectory.text == 'Parent directory/') {
                parentDirectory.classList.add("parent");
            }
        }
    </script>
</head>
<body>
    <h1>