index.html

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Packet Viewer</title>

    <link href="https://maxcdn.bootstrapcdn.com/bootstrap/4.5.2/css/bootstrap.min.css" rel="stylesheet"></link>
    <link href="style.css">
    <style>
        .selected {
            background-color: yellow;
        }
    </style>
</head>
<body>
    <div class="container">
        <h1>Packet Viewer</h1>
        <textarea id="packetInput" class="form-control" rows="8" placeholder="Enter your packet data here"></textarea><br>
        <button onclick="formatHexInput()">Format</button>
        <br><br>
        <p>Click a byte to selected it and display information about it.</p>

        <div class="row mt-4">
            <div class="col-md-6">
                <h2>Hex Data View</h2>
                <div id="hexDataView"></div><br>
                <div id="packetLength"></div>
                <div id="selectedByteInfo"></div>
            </div>
            <div class="col-md-6">
                <h2>ASCII Data View</h2>
                <div id="asciiDataView"></div>
            </div>
        </div>
    </div>

    <script src="https://code.jquery.com/jquery-3.5.1.slim.min.js"></script>
    <script src="https://cdn.jsdelivr.net/npm/@popperjs/core@2.9.2/dist/umd/popper.min.js"></script>
    <script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.5.2/js/bootstrap.min.js"></script>
    <script src="script.js"></script>
</body>
</html>