function is_https(){
if(!empty($_SERVER['HTTPS']) && strtolower($_SERVER['HTTPS']) !== 'off'){
return true;
}elseif(isset($_SERVER['HTTP_X_FORWARDED_PROTO']) && $_SERVER['HTTP_X_FORWARDED_PROTO'] === 'https'){
return true;
}elseif(!empty($_SERVER['HTTP_FRONT_END_HTTPS']) && strtolower($_SERVER['HTTP_FRONT_END_HTTPS']) !== 'off'){
return true;
}
return false;
}