Form Data

<!--Write a PHP script GetFormData.php which retrieves the input data from an HTML form, and displays it as string.
The input fields should hold name, age and gender (radio buttons). The returned string should be a message
containing the information submitted by the form. 100% accuracy is NOT required. Semantic HTML is required.-->

<!DOCTYPE html>
<html>
<head lang="en">
    <meta content="text/html" charset="UTF-8">
    <title>Form Data</title>
    <style type="text/css">
        form {
            margin-bottom: 15px;
        }

        p {
            padding: 2px;
            margin: 0;
        }
    </style>
</head>
<body>
<form action="#" method="post">
    <p><input type="text" name="username" maxlength="25" placeholder="Name..." required/></p>

    <p><input type="number" name="age" min="1" max="100" placeholder="Age..." required/></p>

    <p><input type="radio" name="gender" value="male" id="gender-male" checked="checked"/><label
            for="gender-male">Male</label></p>

    <p><input type="radio" name="gender" value="female" id="gender-female"/><label
            for="gender-female">Female</label></p>
    <input type="submit" value="Submit"/>
</form>
<?php
mb_internal_encoding("UTF-8");
if (count($_POST) == 3) {
    $username = trim($_POST['username']);
    $age = $_POST['age'];
    $gender = $_POST['gender'];

    echo '<p>My name is ' . htmlspecialchars($username) . '. I am ' . htmlspecialchars($age) .
        ' years old. I am ' . htmlspecialchars($gender) . ".</p>\n";
}
?>
</body>
</html>