HTML syntax highlight stops

[sharwell]

Moved here from BitBucket

<?php

$sql_configure = "SELECT * FROM `productconfigurable` WHERE `productid` = '" . $_GET['id'] . "' and `act`='1' ORDER BY `sortorder` asc";
$result_configure = mysql_query($sql_configure);
$count_configure = mysql_num_rows($result_configure);

?>
<style>
div.rectanglebox a.rectangle {
    background-color: #e6e6e6 !important;
    color: #000000 !important;
}
div.rectanglebox a.active {
    background-color: #12799a !important;
    color: #ffffff !important;
}
</style>
<div class="modal-header">
 <button class="close" data-dismiss="modal">X</button>
 <h3>Customize - <?= $info['name'] ?></h3>
</div>

Suppose I have code like this. Then it does not highlight syntax in style tag, as well as it stops html syntax highlighting after occurrence of <?=.