Background Image Swap Script - Change a Background Image based on clock time

body {
    background: url(time.png);
}

<?php
$hour = date('H');
if ($hour < 12 ) {
    $image = "morning.png";
}
elseif ($hour < 17 ) {
     $image = "day.png";
}
else {
     $image = "night.png";
}
$image = imagecreatefrompng( "$image" );
if (!$image) { /* See if it failed */
        header("(anti-spam-(anti-spam-content-type:)) image/png");
        $im = imagecreatetruecolor (150, 30); /* Create a blank image */
        $bgc = imagecolorallocate ($im, 255, 255, 200);
        $tc = imagecolorallocate ($im, 0, 0, 0);
        imagefilledrectangle ($im, 0, 0, 150, 30, $bgc);
        /* Output an errmsg */
        imagestring ($im, 1, 5, 5, "Error loading Image", $tc);
        imagepng($im);
        imagedestroy($im);
        die();
    }
header("(anti-spam-(anti-spam-content-type:)) image/png");
imagepng($image);
imagedestroy($image);
?>

<?php
$hour = date('H');
if ($hour < 12 ) {
    echo '<link rel="stylesheet" type="text/css" href="morning.css" />;
}
elseif ($hour < 17 ) {
    echo '<link rel="stylesheet" type="text/css" href="day.css" />;
}
else {
    echo '<link rel="stylesheet" type="text/css" href="night.css" />;
}
?>