1
<div id="myDIV">2
<h2> h2 元素</h2>3
<h3> h3 元素</h3>4
</div>5
<script>6
var x = document.getElementById("myDIV");7
x.querySelector("h2, h3").style.backgroundColor = "red";8
</script>
<div id="myDIV"> <h2> h2 元素</h2> <h3> h3 元素</h3></div><script> var x = document.getElementById("myDIV"); x.querySelector("h2, h3").style.backgroundColor = "red";</script>