<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
<style>
/* #one {
color: red;
}
.son {
color: blue;
}
p {
color: green;
} */
/* (行内, id, 类, 标签) */
/* (0, 1, 0, 1) */
div #one {
color: orange;
}
/* (0, 0, 2, 0) */
.father .son {
color: skyblue;
}
/* 0, 0, 1, 1 */
.father p {
color: purple;
}
/* 0, 0, 0, 2 */
div p {
color: pink;
}
</style>
</head>
<body>
<div class="father">
<p class="son" id="one">我是一个标签</p>
</div>
</body>
</html>