<!DOCTYPE html>
<html>
<head>
<style>
div { border: 1px solid #FF0000;
}
</style>
</head>
<body>
<div id="myDiv">这是一些文字。</div>
<br>
<button type="button" onclick="changeMargin()">更改 div 元素的底部边距</button>
<br>
<br>
<div id="myDiv2">这是一些文字。</div>
<br>
<button type="button" onclick="changePadding()">更改 div 元素的底部填充</button>
<script>
function changeMargin() { document.getElementById("myDiv").style.marginBottom = "100px";}
function changePadding() { document.getElementById("myDiv2").style.paddingBottom = "100px";}
</script>
</body>
</html>