Web Development

.square{
       height: 50px;
  width: 50px;
  background-color: powderblue;
}
<div class="board-row">
<button class="square">a</button>
<button class="square">
</button><button class="square"></button>
</div>

[HttpGet]
public string Test()
{
    return "Server is running";
}

<Error>
<Message>
No HTTP resource was found that matches the request URI 'http://localhost:49970/API/Test/Test'.
</Message>
<MessageDetail>
No type was found that matches the controller named 'Test'.
</MessageDetail>
</Error>

// both of the specified partial views do in fact exist in the Views/Shared folder
public ActionResult AppInfo()
{
	return View();
}

public ActionResult AppInfoAbout()
{
    return PartialView("_About");
}
public ActionResult AppInfoContact()
{
    return PartialView("_Contact");
}

<!-- the razor vars you see in this sniuppet all contain the appropriate values -->
 <div style="display:flex;flex-direction:row;">
    <div style="width:150px;">
        <a href="@btnLinkAbout"   class="btn btn-primary aef-app-info about-btn">@aboutBtnText</a>
        <br/>
        <a href="@btnLinkContact" class="btn btn-primary aef-app-info contact-btn">Contact Us</a>
    </div>
    <div style="width:850px;">
        <div id="siteInfoContent" >
            <span>Click one of the buttons at the left of this box to view the associated content.</span>
        </div>
    </div>
</div>

<script>
$('.aef-app-info').on('click', function(evt) {
    evt.preventDefault();
    evt.stopPropagation();

    var $contentDiv = $('#siteInfoContent'),
        url = $(this).data('url');

    $.get(url, function(data) { $contentDiv.html(data); });
});
</script>

<script>
        $(document).ready(function () {
            $('[data-toggle="tooltip"]').tooltip();
        });
</script>

Fatal error: Uncaught Error: Call to a member function prepare() on null in C:\xampp\htdocs\gco\core\classes\user.php:16 Stack trace: #0 C:\xampp\htdocs\gco\includes\login.php(15): User->login('rahul@yahoo.com', 'password') #1 C:\xampp\htdocs\gco\index.php(66): include('C:\\xampp\\htdocs...') #2 {main} thrown in C:\xampp\htdocs\gco\core\classes\user.php on line 16

public function login($email,$password){
    $stmt = $this->pdo->prepare("SELECT 'user_id' FROM 'users' WHERE 'email'=:email AND 'password'=:password");
    $stmt->bindParam(":email",$email,PDO::PARAM_STR);
    $stmt->bindParam(":password",md5($password),PDO::PARAM_STR);
    $stmt->execute();