Your entries have no attributes name. Set these options:
<input type="text" id="inputName" placeholder="First name" name="first_name" />
<input type="text" id="inputLastname" placeholder="Last name" name="last_name" >
Also, see how you detect form submission:
if(isset($_POST['send']))
, . , Internet Explorer , .
:
if($_SERVER['REQUEST_METHOD'] == 'POST')
if(isset($_POST['first_name'], $_POST['last_name']))
- Why isset($_POST['submit']) .