活到老学到老，真的是每天都发现自己基础有点问题，实践是检验真理的唯一标准
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
<style>
div{
width: 1000px;
height: 100px;
margin: 50px auto;
text-align: center;
}
.font-exp{
display: block;
letter-spacing: 2px;
transition: all 1s ease-in-out;
font-size: 40px;
font-family: "微软雅黑";
}
.font-exp:hover{
letter-spacing: 5px;
font-size: 45px;
}
</style>
</head>
<body>
<div>
<span class="font-exp">share your code,share your wrold</span>
</div>
</body>
</html>
设置transition的时候，要在状态切换前后，都设置对用属性的值
fontchange.gif
