$sRequestUri = trim( $_SERVER['REQUEST_URI'], '/' );
$sContentFolder = __DIR__ . '/content/';
$sContentFilePath = $sContentFolder . $sRequestUri . '.html';


if ( !is_dir($sContentFilePath) ) {

    header ( 'HTTP/1.0 404 Not Found' );
    $sContentFilePath = $sContentFolder . '404.html';

}

echo file_get_contents( $sContentFilePath );