index.html

<!DOCTYPE html>
<html lang="en">

    <head>

        <meta charset="utf-8">
        <meta name="viewport" content="width=device-width; initial-scale=1.0; maximum-scale=1.0;">

        <title>Enter your first name</title>

        <link rel="stylesheet"  href="assets/css/styles.css" />

    </head>

    <body>

        <label for="firstname">Enter your first name</label>
        <input id="firstname" name="firstname" type="text">
        <p id="namevalidation" class="validation">Swapnil</p>

        <div class="mainContent">
            <p>page section</p>
            <div>
                <span>Test NAME</span>
            </div>
        </div>

        <script type="text/javascript" src="assets/js/jquery-1.10.2.min.js"></script>
        <script type="text/javascript" src="assets/js/main.min.js"></script>

    </body>

</html>