public static function write_error_html($errtitle, $errdetails, $errcode, $backtrace = null) {
		global $USR;
		?>
		<!DOCTYPE HTML>
		<html xmlns="http://www.w3.org/1999/xhtml" lang="en">
			<head>
				<meta charset="UTF-8" />
				<meta http-equiv="Content-Type" content="text/html;charset=utf-8" />
				<title><?php echo $errtitle ?></title>
				<style>
					html {
						background-color: #111;
						font-family: sans-serif;
						color: #fff;
					}
					.errbox {
						margin: 3rem;
						padding: 1rem;
						border-radius: 0.5rem;
						background-color: #500;
						border: 1px solid #f00;
					}
					.errbox h1, .errbox h2, .errbox h4 {
						margin: 0;
						padding: 0;
					}
					.errbox h1 {
						text-align: center;
						margin: 1rem 1rem 2rem;
					}
					.errbox h4 {
						margin-bottom: 1rem;
					}
					.errbox > div {
						background-color: #300;
						border: 1px solid #800;
						padding: 1rem;
					}
				</style>
			</head>
			<body>
				<div id="page">
					<div id="subContent">
						<div class="errbox">
							<?php
								echo '<h1>'.$errcode.': '.$errtitle.'</h1>';
								if (!empty($errdetails)) {
									echo '<div><h2>'.$errdetails.'</h2></div>';
								}
								if (!empty($USR) && $USR->is_admin === true && !empty($backtrace)) {
									echo '<div><h4>Backtrace:</h4>'.$backtrace.'</div>';
								}
							?>
						</div>
					</div>
				</div>
			</body>
		</html>
		<?php
	}