<!doctype html>
<style>
 html { color: red }
</style>
<dialog id=dialog-closed></dialog>
<dialog id=dialog-open open></dialog>
<dialog id=dialog-modal></dialog>
<script>
window.dialogClosed = document.getElementById('dialog-closed');
window.dialogOpen = document.getElementById('dialog-open');
window.dialogModal = document.getElementById('dialog-modal');
dialogModal.showModal();
</script>
