Decode PHP gzuncompress base64 encryption

<?php
/*
 * Coded By AJITH KP aka 0x4j17# aka c0bra
 * visit http://www.terminalcoders.blogspot.in
*/
if(isset($_REQUEST['encryptedtxt']))
{
$encrypted=$_REQUEST["encryptedtxt"];
$decrypted=gzuncompress(base64_decode($encrypted));
$tmp=fopen("decrypted.txt" , "w");
fwrite($tmp, $decrypted);
$file="decrypted.txt";
if (file_exists($file)) {
    header('Content-Description: File Transfer');
    header('Content-Type: application/octet-stream');
    header('Content-Disposition: attachment; filename='.basename($file));
    header('Content-Transfer-Encoding: binary');
    header('Expires: 0');
    header('Cache-Control: must-revalidate');
    header('Pragma: public');
    header('Content-Length: ' . filesize($file));
    ob_clean();
    flush();
    readfile($file);
    exit;
}
ignore_user_abort(true);
if (connection_aborted()) {
unlink($f);
fclose($tmp);
}
}
echo "<style>
textarea { font-size:medium;width:900px; height: 350px; border: 2px solid green; background-color:black; color: green; font-size:103%; }
button { background-color:black; color:green; border: 1px solid green; }
html { background:url(http://www.ajithkp560.hostei.com/images/background.gif) black; }
input { background-color:black; color:green; border:1px solid green; }
.container { background-color: black; color: green; border:1px solid green; -moz-border-radius: 10px; border-radius: 10px; width:960px; font-size=15px; }
</style>
<title>PHP Decrypter</title><center>
<div class='container'><h1>gzuncompress Decrypter</h1></div><br />
<form method='post'>
<textarea name='encryptedtxt' cols='25' rows='10' onfocus='if (this.value == \'input the text inside here\'){this.value = \'\';}>input the text inside here</textarea><br /><br /><input type=submit value='>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>'></form><br/>";
?>
<div style="border:1px solid green;width:960px; height:70px; color:green; background-color:black;"><p><font size=4>Input The gzuncompress base64 encryption</font></p></div></center>