chromium/third_party/blink/web_tests/http/tests/security/resources/cors-style.php

<?php
$cors_arg = strtolower($_GET["cors"] ?? "");
if ($cors_arg != "false") {
    if ($cors_arg == "" || $cors_arg == "true") {
        header("Access-Control-Allow-Origin: http://127.0.0.1:8000");
    } else {
        header("Access-Control-Allow-Origin: " . $cors_arg . "");
    }
}
if (strtolower($_GET["credentials"] ?? "") == "true") {
    header("Access-Control-Allow-Credentials: true");
}
header("Content-Type: text/css");
echo ".id1 { background-color: yellow }";
?>