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本文档使用
php.cn手册 发布
文字
说明：
相对长度单位。相对于当前对象内文本的字体尺寸。
如当前对行内文本的字体尺寸未被人为设置，则相对于浏览器的默认字体尺寸。
兼容性：
| IE | Firefox | Chrome | Safari | Opera | iOS Safari | Android Browser | Android Chrome |
|---|---|---|---|---|---|---|---|
| 6.0+ | 2.0+ | 4.0+ | 3.1+ | 3.5+ | 3.2+ | 2.1+ | 18.0+ |
示例：
实例
<!DOCTYPE html>
<html lang="zh-cmn-Hans">
<head>
<meta charset="utf-8" />
<title>em_CSS参考手册_web前端开发参考手册系列</title>
<meta name="author" content="Joy Du(飘零雾雨), dooyoe@gmail.com, www.doyoe.com" />
<style>
body { font-size: 14px; }
h1 { font-size: 16px; }
.size1 p { font-size: 1em; }
.size2 p { font-size: 2em; }
.size3 p { font-size: 3em; }
</style>
</head>
<body>
<h1>假定当前默认字体尺寸是14px，n em即为14px字体尺寸的n倍：</h1>
<ul>
<li class="size1">
<strong>1em</strong>:
<p>1em大小的文字</p>
</li>
<li class="size2">
<strong>2em</strong>:
<p>2em大小的文字</p>
</li>
<li class="size3">
<strong>3em</strong>:
<p>3em大小的文字</p>
</li>
</ul>
</body>
</html>
运行实例 »
点击 "运行实例" 按钮查看在线实例