"%":是继承父级元素的距离;
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
<style>
body{
font-size:14px;
line-height:150%;
background: black;
}
p{
font-size:26px;
background: gray;
color: white;
}
</style>
</head>
<body>
<p>你好!</p>
</body>
</html>
效果如图:

<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
<style>
body{
font-size:14px;
line-height:1.5;
background: black;
}
p{
font-size:26px;
background: gray;
color: white;
}
</style>
</head>
<body>
<p>你好!</p>
</body>
</html>
效果如图:

line-height:150%和line-height:1.5的区别
原文:http://www.cnblogs.com/Yirannnnnn/p/4846382.html