<!DOCTYPE html>
<html>
<head>
<title>Iframe Content</title>
<style>
#first, #second {
border: 1px solid #ccc;
margin: 2px;
padding: 10px;
}
</style>
</head>
<body>
<p>This is the content of the iframe.</p>
<div id="first" aria-label="div1_label">This is the first div.</div>
<div id="second" aria-label="div2_label">This is the second div.</div>
</body>
<script>
window.addEventListener('load', function() {
if (window.parent && window.parent.iframeLoaded) {
window.parent.iframeLoaded();
}
});
</script>
</html>