代码:

<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        #i1{
            background-color: blue;
    }
        .c1{
            background-color: beige;
        }
        span{
            background-color: aqua;
        }
        div span{
            background-color: red;
        }
        #c2,.c3,p{
            background-color: black;
            color: white;
        }
        input[type="test"]{
            width: 100px;
            height: 200px;
        }
    </style>

</head>
<body>
    <div id="i1">id选择器属性</div>
    <div class="c1">class选择器属性</div>
    <span>标签选择器属性</span>
    <div><span>层级选择器</span></div>
    <div id="c2">组合选择器的c2</div>
    <p>组合选择器的p</p>
    <div class="c3">组合选择器的.c3</div>
    <input type="test">
</body>
</html>

展示