Use Strict-Transport-Security (STS) to force the use of SSL.

body{ background:linear-gradient(-10deg,white,#ccc); } Use Strict-Transport-Security (STS) to force the use of SSL.
<?php
$use_sts = TRUE;

if ($use_sts && isset($_SERVER['HTTPS']) {
  header('Strict-Transport-Security: max-age=500');
} elseif ($use_sts && !isset($_SERVER['HTTPS']) {
  header('Status-Code: 301');
  header('Location: https://'.$_SERVER["HTTP_HOST"].$_SERVER['REQUEST_URI']);
}?>