1，css引入
<title>CSS简介与引入</title>
<style>
p{
coler:green;
}
</style>
</head>
<body>
<p style="color:red">战神你好</p>
</body>
==========================================CSS引入
<head>
<meta charset="UTF-8">
<title>外部CSS样式引入</title>
<link rel="stylesheet" href="style11.css">
</head>
<body>
<p>aaaaaa</p>
<p>AAAAAAA</p>
<P>CCCCAAAAA</P>
</body>
CSS样式优先级
<title>CSS样式优先级</title>
<style>
/*id 选择器*/
#red{
color:red;
}
/*标签选择器*/
p{
color:darkgreen;
}
/*类选择器*/
.blue{
color:blue;
}
</style>
</head>
<body>
<p id="red">这个是id选择器</p>
<p>这个是标签选择器</p>
<p class="blue">这个是类选择器</p>
</body>
一切皆是盒子
<head>
<meta charset="UTF-8">
<title>一切皆是是盒子</title>
</head>
<body>
<video src="static/images/demo.mp4" controls width="500" height="280" poster="static/images/bg.jpg"></video>
<ul>
<li class="item">1<a href="">最新产品</a> </li>
<li class="item">2<a href="">最新产品</a> </li>
<li class="item">3<a href="">最新产品</a> </li>
<li class="item">4<a href="">最新产品</a> </li>
</ul>
</body>