使用php和postfix发送邮件

Thank you for taking the time to review my question. I have postfix set up on Centos 6.4 I am not very familiar with E-mail servers or PHP, but I would like to set up a simple sight to send emails using postfix. I was told I should use php. My current. (not working) source code is this...

<!doctype html>
<html>
<head>
<style type="text/css">
#mainContainer
{
        position: absolute;
        top: 0;
        right: 0;
        bottom: 0;
        left: 0;
}

#adressContainer
{
        width:100%;
        height:3%;
}

#buttonContainer
{
        width:100%;
        height:5%;
}

#bodyContainer
{
        width:100%;
        height:90%;
}

#address
{
        resize:none;
        width:100%;
        height:100%;
}

#bodyText
{
        resize:none;
        width:100%;
        height:100%;
}
</style>
<script>

        <?php
        function sendMail()
        {

                $to = "someone@somewhere"
                $subject = "Test mail";
                $message = "Hello! This is a simple email message.";
                $headers = "From:" . $from;
                mail($to,$subject,$message,$headers);
        }       
        ?>
</script>
<!--<link rel="stylesheet" type="text/css" href="email.css" />-->
</head>
<body>
        <div id="mainContainer">
                <div id="addressContainer">
                        <input id="adress" type="text" name="Adress: "></input>
                </div>

                <div id="buttonContainer">
                        <button type="submit" onclick="sendMail()">send</button>
                </div>

                <div id="bodyContainer">
                        <textarea id="bodyText">I love you whitney :) </textArea>
                </div>
        </div>
</body>
</html>

PHP runs on the server. onClick executes Javascript on the CLIENT machine. You can NOT directly invoke PHP functions via Javascript code, or vice versa.

What you're doing can be accomplished with a simple form:

<?php

if ($_SERVER["REQUEST_METHOD"]  == 'POST') {
    $to = $_POST['to'];
    $text = $_POST['text'];
    mail($to, .....);
}

?>
<form method="POST" action="">
    <input type="text" name="to" />
    <input type="text" name="text" />
    <input type="submit" />
</form>

There is no need to use Javascript at all.