zoukankan      html  css  js  c++  java
  • CSS关键点

    写的位置:

    <head>
        <meta charset="UTF-8">
        <title>Title</title>
        <style>
            css样式所在
        </style>
    
    </head>

    注释:

    /*  注释内容 */

    id选择器:标签id对应样式

    <!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>Title</title>
        <style>
            #i1 {
                background-color: red;
                height: 48px;
            }
        </style>
    
    </head>
    <body>
        <div id="i1"></div>
    </body>
    </html>
    例子

    class选择器:.样式名称

    <!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>Title</title>
        <style>
            .c1{
                background-color: red;
                height: 48px;
            }
        </style>
    
    </head>
    <body>
        <div class="c1"></div>
    </body>
    </html>
    eg

    标签选择器:所有标签对应的应用样式

    <!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>Title</title>
        <style>
            div{
                background-color: red;
                height: 48px;
            }
        </style>
    
    </head>
    <body>
        <div class="c1"></div>
    </body>
    </html>
    所有的dvi标签都使用该样式

    层级选择器(关联选择器):空格分隔

    <!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>Title</title>
        <style>
            span div{
                background-color: red;
                height: 48px;
            }
        </style>
    
    </head>
    <body>
        <span>
            <div></div>
        </span>
    </body>
    </html>
    span标签下的div使用样式
    <!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>Title</title>
        <style>
            .c1 div{
                background-color: red;
                height: 48px;
            }
        </style>
    
    </head>
    <body>
        <span class="c1">
            <div></div>
        </span>
    </body>
    </html>
    class为c1的标签下的div使用样式

    组合选择器,逗号分隔

    <!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>Title</title>
        <style>
            .c1,.c2,.c3 div{
                background-color: red;
                height: 48px;
            }
        </style>
    
    </head>
    <body>
        <span class="c1"></span>
        <div class="c2"></div>
        <div class="c3"></div>
    </body>
    </html>
    eg

    属性选择器:对选择到的标签再通过属性进行一次筛选

    <!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>Title</title>
        <style>
           input[type='text']{
               width: 100px;
               height: 200px;
           }
        </style>
    
    </head>
    <body>
        <input type="text" />
    </body>
    </html>
    input标签type为text的才使用样式
    <!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>Title</title>
        <style>
           input[n='alex']{
               width: 100px;
               height: 200px;
           }
        </style>
    
    </head>
    <body>
        <input type="text" n="alex"/>
    </body>
    </html>
    eg
    <!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>Title</title>
        <style>
           .c1[n='alex']{
               width: 100px;
               height: 200px;
           }
        </style>
    
    </head>
    <body>
        <input class="c1" type="text" n="alex"/>
    </body>
    </html>
    eg2

    css优先级:标签上style优先,编写顺序,就近原则

    标签上的style优先级最高,优先显示这个,stype标签里面的,越往下,优先级越高,这里c2在c1下方,所以c1相同样式不使用

    <!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>Title</title>
        <style>
           .c1{
               background-color: red;
               color: white;
           }
            .c2{
                font-size: 58px;
                color: black;
            }
        </style>
    
    </head>
    <body>
        <div class="c1 c2" style="color: #2b542c"></div>
    </body>
    </html>
    eg

    css样式引用

    <!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>Title</title>
        <link rel="stylesheet" href="index.css">
       
    
    </head>
    <body>
        
    </body>
    </html>
    link标签引用

    css属性

    边框:border,可以分上下左右

    <!-- 边框大小为1,实线,红色 -->
    <div style="border: 1px solid red;"></div>
    width            宽度
    height:48px;        标签高度48px
    font-size:16px;      字体大小
    text-align:center;    水平居中
    line-height:48px;    根据高度填写数值,这里会垂直居中
    font-weight:blod    字体加粗

    float  让标签浪起来,块级标签页可以堆叠

        <!-- 将两个div标签放到同一行-->
        <div style=" 20%;background-color: red;float: left">1</div>
        <div style=" 80%;background-color: black;float: left">2</div>

    管不住子标签的时候,可以用下面的语句将标签弄出来

    <div style="clear: both;"></div>

    display 

    display:inline;         变成行内标签
    display:block; 变成块级标签
    display:none;       让标签消失

      display:inline-block;
      1.具有inline,默认自己又多少占多少
      2.具有block,可以设置高度,宽度

     
        <div style="background-color: red;display: inline">变成行内标签</div>
        <span style="background-color: red;display: block">变成块级标签</span>

    position

    position:fixed 固定页面某个位置(相对位置)

    <!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>Title</title>
    </head>
    <body>
    {#位置固定,相对路径,bottom离底部20px,right离右侧20px#}
    <div onclick="GoTop()" style=" 50px;height: 50px;background-color: black;color: white;
    position: fixed;
    bottom: 20px;
    right: 20px;
    ">返回顶部</div>
        <div style="height: :5000px;background-color: #DDDDDD"></div>
    
        <script>
            function GoTop() {
                document.body.scrollTop = 0;
            }
        </script>
    </body>
    </html>
    右下角返回顶部操作
    <!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>Title</title>
        <style>
            .pg-header{
                height: 48px;
                background-color: black;
                color: #DDDDDD;
                position: fixed;/* 固定位置,下方三个组合,成为顶部菜单*/
                top: 0;
                left: 0;
                right: 0;
            }
            .pg-body{
                background-color: #DDDDDD;
                height: 5000px;
                margin-top: 48px;/* 离开头部48px*/
            }
        </style>
    </head>
    <body>
        <div class="pg-header">头部</div>
        <div class="pg-body">内容</div>
    </body>
    </html>
    顶部菜单

    position:absolute 固定页面某个位置(绝对位置)

    <!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>Title</title>
    </head>
    <body>
        <!-- 绝对位置的固定-->
        <div style=" 50px;height: 50px;background-color: black;position: absolute;bottom: 0;right: 0">头部</div>
        <div style="height: 5000px;background-color: #DDDDDD">内容</div>
    </body>
    </html>
    固定某个位置,不变了

    一般是relative + absolute使用(单独relative 没作用)

    <!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>Title</title>
    </head>
    <body>
        <div style="position: relative; 500px;height: 200px;border: 1px solid red;margin: 0 auto">
            <div style="position: absolute;left: 0;bottom: 0; 50px;height: 50px;background-color: black"></div>
        </div>
        <div style="position: relative; 500px;height: 200px;border: 1px solid red;margin: 0 auto">
            <div style="position: absolute;right: 0;bottom: 0; 50px;height: 50px;background-color: black"></div>
    
        </div>
        <div style="position: relative; 500px;height: 200px;border: 1px solid red;margin: 0 auto">
            <div style="position: absolute;right: 0;top: 0; 50px;height: 50px;background-color: black"></div>
    
        </div>
    </body>
    </html>
    某个div里面的绝对位置


    opacity: 0.5; 透明度,0为没有,1是完全遮盖

    <!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>Title</title>
    </head>
    <body>
       <div style="position: fixed;background-color: black;top: 0;left: 0;right: 0;bottom: 0;
        opacity: 0.5;"></div>
        <div style="height: 5000px;background-color: #DDDDDD"></div>
    </body>
    </html>
    遮罩层

    z-index:10 层级顺序 哪个值大,就在上面显示

    <!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>Title</title>
    </head>
    <body>
       <div style="z-index: 10; position: fixed;background-color:white; 400px;height: 500px;
       top: 50%;left: 50%;margin-left: -250px;margin-top: 200px /*组合成为居中*/
    "></div>
       <div style="z-index: 9; position: fixed;background-color: black;top: 0;left: 0;right: 0;bottom: 0;
        opacity: 0.5;"></div>
        <div style="height: 5000px;background-color: #DDDDDD"></div>
    </body>
    </html>
    三层分层

     overflow:hidden 图片或者其他超出div大小则隐藏

    <!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>Title</title>
    </head>
    <body>
        <div style="height: 200px; 300px;overflow: hidden">
            <img src="1.jpg" />
        </div>
    </body>
    </html>
    eg

    overflow:auto 图片或者其他超出div大小则出现滚动条

    <!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>Title</title>
    </head>
    <body>
        <div style="height: 200px; 300px;overflow: auto">
            <img src="1.jpg" />
        </div>
    </body>
    </html>
    eg

    padding:10px; 标签上下左右均为10px
    padding:0 10px; 上下为0,左右为10px;
    padding:0 10px 0 10px; 上右下左

    hower:鼠标移动到这里,css样式生效

    <!DOCTYPE html>
    <html lang="en">
    <head>
        <meta charset="UTF-8">
        <title>Title</title>
        <style>
            .menu:hover{
                background-color: blue;
            }
        </style>
    </head>
    <body>
        <div  style="height: 200px; 300px;overflow: auto;">
                <a class="menu">鼠标移动到这里背景颜色变更</a>
        </div>
    </body>
    </html>
    eg

    background-image:url('image/1.jpg'); # 默
    认,div大,图片会重复访问,无论是水平还是垂
    直(这个可以小图片,制作出页面的渐变色)
    background-repeat(no-repeat) # 无叠加
    background-repeat(repeat-x) # 只水平叠加
    background-repeat(repeat-y) # 只垂直叠加

    一张图片有多个图标使用的情况
    background-position 10px 10px;  
    background-position-x 图片显示左右移动
    background-position-y 图片显示上下移动

    background:url('image/1.jpg' 10px; 20px; no-repeat)

    # 相当于:
    background-image:url('image/1.jpg');
    background-position-x 10px;
    background-position-y 20px
    background-position-y    

    bxslider插件,可以做到循环播放

    注意:

    行内标签:无法设置高度,宽度,边距

  • 相关阅读:
    SignalR客户端和服务端编写,winfrom端
    SQL 发送邮件msdb.dbo.sp_send_dbmail
    Stimulsoft打印内容横向,变成竖向,解决方法
    Chrome浏览器所有页面崩溃
    SQL存储过程直接传表
    c#SignalR一次发送最大数据量
    c#USB扫描枪,防止输入框手动输入
    SQLPrompt_9.5.5.9830破解版含注册机_永久激活不掉线
    SQL快捷键设置
    USB HDI 通信
  • 原文地址:https://www.cnblogs.com/cheng662540/p/9813217.html
Copyright © 2011-2022 走看看