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<body>
<h1>The Document Object</h1>
<h2>The querySelector() Method</h2>
<p>Add a background color to the first p element with class="example".</p>
<h2 class="example">A heading</h2>
<p class="example">A paragraph.</p>
<script>
document.querySelector("p.example").style.backgroundColor = "red";
</script>
</body>
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