css属性3

css属性,只有块级标签设计宽和高才会生效:

<!DOCTYPE html>
<html lang="zh-CN">
<head>
    <meta charset="UTF-8">
    <title>选择器的优先级</title>
    <link rel="stylesheet" href="zz.css" type="text/css">
    <style>
        .c1 {
            width: 360px;
            height: 200px;
            background-color: #75b976;}
        span {
width: 100px;
    height: 120px;
    background-color: #20201c;
    font-size: 44px;
    font-weight: 800;
    font-color: yellow;
    color: white;
    color:#FFFFFF;
    color:rgba(255,255,255,0.5)
        }
        a{
    text-decoration: none;
}
    </style>
</head>
<body>

<div class="c1">div</div>
<div>div1</div>
<span>我是span</span>
<a href="https://www.baidu.com">baidu</a>
<p></p>
</body>
</html>

 选择器的优先级

<!DOCTYPE html>
<html lang="zh-CN">
<head>
    <meta charset="UTF-8">
    <title>选择器的优先级</title>
    <link rel="stylesheet" href="zz.css" type="text/css">
    <style>
        .c1 {
            width: 360px;
            height: 200px;
            background-color: #75b976;}
        span {
width: 100px;
    height: 120px;
    background-color: #20201c;
    font-size: 44px;
    font-weight: 800;
    font-color: yellow;
    color: white;
    color:#FFFFFF;
    color:rgba(255,255,255,0.5)
        }
        a{
    text-decoration: none;
}
    </style>
</head>
<body>

<div class="c1">div</div>
<div>div1</div>
<span>我是span</span>
<a href="https://www.baidu.com">baidu</a>
<p></p>
</body>
</html>

 display:''inline-block" 既有行内标签又有块级标签的作用

display: none 

边框

<!DOCTYPE html>
<html lang="zh-CN">
<head>
    <meta charset="UTF-8">
    <title>边框</title>
    <style>
        .c1{
            display:block;
        }
        .c3, .c4 {height:100px;
                width:100px;
                background-color:blue;
                border:1px solid green;}
        .c4{
            background-color:red;
        }
        <!--.c3{-->
        <!--display:none;}-->
    </style>
</head>
<body>
<span class="c1">这是一个span</span>
<span>这是一个span</span>
<hr>
<div class="c3"></div>
<div class="c4"></div>
</body>
</html>

盒子模型:

<!DOCTYPE html>
<html lang="zh-CN">
<head>
    <meta charset="UTF-8">
    <title>盒子模型</title>
    <!--magin:外边距  border: 边框  padding  内填充   content 内容-->
    <style>
        .c1{
        width:200px;
        height:100px;
        background-color: red;
        margin: 10px auto
    }
        .c2{
        margin-top:25px;
        border: solid black;
        background-color:blue;
        padding: 10px 20px 30px 40px;
        /*<!--padding-top:20px;-->
        <!--padding-buttom:25px;-->
        <!--padding-left:30px;-->
        <!--padding-right:40px;--> 还是得用这个注释,不然后面的css不能读出来*/
        /*padding: 10px 20px 30px 40px;*/
    }
    </style>
    <!--设置外边距的距离以最大的来看-->
</head>
<body>
<div class="c1"></div>
<div class="c2">111</div>
</body>
</html>

浮动

<!DOCTYPE html>
<html lang="zh-CN">
<head>
    <meta charset="UTF-8">
    <title>浮动</title>
    <style>
    /*.left{
        background-color: #4d4d4d;
        height: 600px;
         20%;
        float:left;
    }
    .right{
        background-color: red;
        height: 600px;
        80%;
        float:right;
    }*/
    body{
        margin:0;
    }
    .c1{
        border:1px solid black;
    }
    .c2{
        height: 50px;
        width: 50px;
        background-color: red;
        border:1px solid blue;
        float:left;
    }
    .c3{
        height: 100px;
        background-color: yellow
    }
    .c4{
        clear:left
    }
    </style>
    <!--clear 属性可以设置哪一侧没有浮动,浮动的弊端,如果有浮动,后面的元素会自动填充到原本的元素里面
    解决方法,添加一个div 设置clear 也可以用伪元素标签 .c1:after{ content:""; clear:left;display:block;}-->
</head>
<body>
<!--<div class="left"></div>-->
<!--<div class="right"></div>-->
<div class="c1">
    <div class="c2"></div>
    <div class="c2"></div>
    <div class="c4"></div>
</div>
<div class="c3"></div>
</body>
</html>

溢出

<!DOCTYPE html>
<html lang="zh-CN">
<head>
    <meta charset="UTF-8">
    <title>溢出</title>
    <style>
        .c1{
            width: 50px;
            height: 50px;
            border: 1px solid black;
            overflow: scroll;
        /*    溢出visible默认值,hidden超出部分被删减 scroll内容被修建,浏览器以滚动条以便查看其余的内容 auto如果被修建,会显示滚动条 */
        }
        .c2{
            height: 128px;
            width: 128px;
            border: 3px solid green;
            border-radius: 50%;
            overflow: hidden;
        }
        .c2>img{
            width: 100%;
        }
    </style>
</head>
<body>
<div class="c1">
    富强民主 在昨天的日子里 今天我们也应当 前世不做
</div>
<div class="c2"><img src="timg.jpg" alt=""></div>
<!--头像-->
</body>
</html>

定位

<!DOCTYPE html>
<html lang="zh-CN">
<head>
    <meta charset="UTF-8">
    <title>定位</title>
    <style>
        body{
            margin: 0;
        }
        .c{
            width: 200px;
            height: 200px;
        }
        .c1{
            background-color: red;
        }
        .c2{
            background-color: green;
            position: relative;
            left: 100px;
        /*    相对定位 相对于祖先元素*/
        }
        .c3{
            background-color: blue;
            position: absolute;
            left: 200px;
            top: 0;
        /*    绝对定位,依次向上找到最近的父标*/
        }
        .c4{
            height: 20px;
            width: 20px;
            color: white;
            background-color: lawngreen;
            font-size: 12px;
            position: fixed;
            right: 25px;
            bottom: 25px;
        }
    </style>
</head>
<body>
<div class="c c1"></div>
<div class="c c2"></div>
<div class="c c3"></div>
<div class="cc c4"></div>
</html>
原文地址:https://www.cnblogs.com/yfjly/p/10926549.html