44.CSS定位
position特性
css position属性用于指定一个元素在文档中的定位方式。op、right、bottom、left属性则决定了该元素的最终位置
position取值
static
relative
absolute
fixed
sticky
relative:
如果没有定位偏移量,对元素本身没任何影响
不是元素脱离文档流
不印象其他元素布局
left、top、right、bottom师弟当前元素自身进行偏移的
absolute:
使元素脱离文档流
使内联元素支持宽高(让内联具备块特性)
使块元素默认宽根据内容决定 (让内联元素具有内联特性)
如果有定位相对于定位祖先员素发生偏移,没有定位祖先相对于整个文档发生偏移(绝对、相对、固定)
fixed固定定位
使元素脱离文档流
使内联元素支持宽高(让内联具备块特性)
使块元素默认宽根据内容决定 (让内联元素具有内联特性)
相对整个浏览器窗口进行偏移,不受浏览器滚动条的影响
stickey定位:
在指定的位置进行黏性操作
代码(position定位让图片居中):
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
<style>
#box1{width:100px;height: 100px;background: red;}
#box2{width:100px;height: 100px;background: blue;position: relative;left:100px;top:100px; }
#box3{width:100px;height: 100px;background: yellow;}
</style>
</head>
<body>
<div id="box1"></div>
<div id="box2"></div>
<div id="box3"></div>
</body>
</html>
代码(position定位):
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
<style>
/* body{height: 2000px;}
div{position:fixed;} */
body{height:2000px;}
#box1{width: 300px;height: 300px;border:1px black solid;margin:200px;position: relative;}
#box1{width: 100px;height: 100px;border:1px black solid;margin:200px;position: relative;}
</style>
</head>
<body>
<!-- <div>这是一个块</div> -->
<div id="box1">
<div id="ox2"></div>
</div>
</body>
</html>
代码(下拉菜单):
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
<style>
*{margin:0;padding:0;}
ul{list-style: none;}
#menu{width: 100px;height: 30px;margin:20px auto;border:1px black solid; position:relative;}
#menu ul{width: 100px;border: 1px black solid;position:absolute;left:-1px;top: 30px;background:white;
display:none;
}
p{text-align: center;}
#menu:hover ul{display:block;}
#menu ul li:hover{background: grey;}
</style>
</head>
<body>
<div id="menu">
卖家中心
<ul>
<li>列表项1</li>
<li>列表项2</li>
<li>列表项3</li>
<li>列表项4</li>
</ul>
</div>
<p>测试段咯</p>
</body>
</html>
45.CSS添加省略号
width
必须有一个固定的宽
white-space:nowrap
不让内容折行
overflow:hidden
隐藏一处的内容
text-overflow:ellipsis
添加省略号
46.CSS Sprite
特性
CSS雪碧也叫CSS精灵,是一种网页图片引用处理方式。它语序你将一个页面设计到的所有零星图片都包含到一张大图中去加载。
好处:
可以减少图片的质量,网页的图片加载速度快
减少图片请求次数,加快网页打开
47.CSS圆角
border-radius
给标签添加圆角。
代码:
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Documen</title>
<style>
/* #box{width: 200px;height: 200px;background:red ;border-radius:100px; } */
/* #box{width: 300px;height: 300px;background:red ;border-radius:50%; } */
/* #box{width: 300px;height: 300px;background:red ;border-radius:10px 20px; } */
#box{width: 300px;height: 300px;background:red ;border-radius:150px 150px 0 0; }
</style>
</head>
<body>
<div id="box"></div>
</body>
</html>
PC布局
通栏:自适应浏览器的宽度
版心:固定一个宽度,让容器居中
代码:
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>Document</title>
<link rel="stylesheet" href="./commen.css">
<style>
#banner{position: relative;}
#banner .banner_list{width: 100%;height: 469px;position: relative;}
#banner .banner_list li{width: 100%;height: 100%;background:center 0 no-repeat;position: absolute;left: 0;top: 0;opacity: 0;z-index: 10;}
#banner .banner_list a{display: block;width: 100%;height: 100%;}
#banner .banner_btn{width: 100%;position: absolute;bottom: 19px;z-index: 20;font-size: 0;text-align: center;}
#banner .banner_btn li{display: inline-block;width: 12px;height: 12px;border: 2px solid white;border-radius: 50%;box-sizing: border-box;margin: 6px;}
#banner .banner_btn li.active{background-color: white;}
#service{overflow: hidden;min-height: 407px;}
#service .service_list{text-align: center;margin-top: 34px;}
#service .service_list li{float: left;width: 250px;margin: 0 10px;}
#service .service_list div{width: 102px;height: 102px;}
#service .service_list li:nth-of-type(1) div{background-image: url(./images/web1.png);}
#service .service_list li:nth-of-type(2) div{background-image: url(./images/web2.png);}
#service .service_list li:nth-of-type(3) div{background-image: url(./images/web3.png);}
#service .service_list li:nth-of-type(4) div{background-image: url(./images/web4.png);}
#service .service_list h3{font-size: 18px; color: #434343;line-height: 36px;margin-top: 25px;}
#service .service_list p{font-size: 14px;color: #6D6D6D;line-height: 22px;}
#case{background: #f8f8f8;}
#case .container{min-height: 460px;overflow: hidden;}
#case .area_title{margin-top: 55px;}
#case .area_title h2{counter-reset: #66C5B4;}
#case .case_list{margin-top: 28px;}
#case .case_list li{float: left;width: 340px;margin: 0 10px;}
#case .case_btn{width: 176px;height: 37px;background: #66C5B4;margin: 0 auto;border-radius: 25px;line-height: 37px;text-align: center;font-size: 14;margin-top: 36px;}
#case .case_btn a{display: block;width: 100%;height: 100%;color: white;}
#news{min-height: 450px;overflow: hidden;}
#news .area_title{margin-top: 65px;}
#news dl{margin-top: 48px;}
#news dt{float: left;width: 234px;}
#news dd{width: 846px;}
#news .news_list{width: 100%;}
#news .news_list li{width: 50%;float: left;margin-bottom: 48px;}
#news .news_date{width: 71px;border-right: 1px solid #DCDCDC;text-align: center;}
#news .news_date i{color: #66C5B4;font-size: 39px;display: block;font-weight: bold;}
#news .news_date span{color: #999999;font-size: 20px;line-height: 36px;}
#news .news_text{width: 310px;margin-left: 20px;}
#news .news_text h3{font-size: 14px;}
#news .news_text h3 a{color: #3F3F3F;}
#news .news_text p{color: #A4A4A4;font-size: 12px;line-height: 21px;margin-top: 17px;}
</style>
</head>
<body>
<div id="head" class="container">
<div class="head_logo l">
<a href="#">
<img src="./images/logo.png" alt="博文尚美" title="博文尚美">
</a>
</div>
<ul class="head_menu r">
<li>
<a href="#">HOME</a>
</li>
<li>
<a href="#">ABOUT</a>
</li>
<li>
<a href="#">PROTFOLIO</a>
</li>
<li>
<a href="#">SERVICE</a>
</li>
<li>
<a href="#">NEWS</a>
</li>
<li>
<a href="#">CONTACT</a>
</li>
</ul>
</div>
<div id="banne" class="contaner-fluid">
<ul class="banner_list">
<li class="active" style="background-image: url(../images/banner.png);">
<a href="#"></a>
</li>
<li style="background-image: url(../images/banner.png);">
<a href="#"></a>
</li>
<li style="background-image: url(../images/banner.png);">
<a href="#"></a>
</li>
<li style="background-image: url(../images/banner.png);">
<a href="#"></a>
</li>
</ul>
<ol class="banner_btn">
<li class="active"></li>
<li></li>
<li></li>
<li></li>
</ol>
</div>
<div id="service" class="comtainer">
<div class="area_title">
<h2>服务范围</h2>
<p>OUR SERVICES</p>
</div>
<ul class="service_list">
<li>
<div></div>
<h3>1.web design</h3>
<p>
企业品牌网站设计/手机网站制作
<br>
动画网站创意设计
</p>
</li>
<li>
<div></div>
<h3>2.graphic design</h3>
<p>
标志logo设计/产品宣传册设计
<br>
企业广告/海报设计
</p>
</li>
<li>
<div></div>
<h3>3.e-business plan</h3>
<p>
淘宝/天猫装修设计及运营推广
<br>
企业微博、微信营销
</p>
</li>
<li>
<div></div>
<h3>4.mailboxagents</h3>
<p>
腾讯/网易企业邮箱品牌代理
<br>
个性化邮箱定制开发
</p>
</li>
</ul>
</div>
<div id="case" class="container-fluid">
<div class="comtainer">
<div class="area_title"></div>
<h2>{客户案例}</h2>
<p>With the best professional technology, to design the best innovative web site</p>
</div>
<ul class="case_list" clear>
<li>
<a href="#"><img src="./images/20141121095216750.png" alt=""></a>
</li>
<li>
<a href="#"><img src="./images/20141121095528549.png" alt=""></a>
</li>
<li>
<a href="#"><img src="./images/20141121105856226.png" alt=""></a>
</li>
</ul>
<div class="case_btn">
<a href="#">VIEW MORE</a>
</div>
</div>
<div id="news" class="container">
<div class="area_title">
<h2>最新资讯</h2>
<p>THE LATEST NEWS</p>
</div>
<dl>
<dt>
<img src="./images/xs1.png" alt="">
</dt>
<dd>
<ul class="news_list">
<li>
<div class="news_date" l>
<i>09</i>
<span>Jan</span>
</div>
<div class="news_text" l>
<h3><a href="#">网站排名进入前三的技巧说明</a></h3>
<p>有很多客户都会纳闷为什么自己的网站老是优化不到搜索引擎
首页,更不用说进首页前三了,那么网站优...
</p>
</div>
</li>
<li>
<div class="news_date" l>
<i>09</i>
<span>Jan</span>
</div>
<div class="news_text" l>
<h3><a href="#">网站排名进入前三的技巧说明</a></h3>
<p>有很多客户都会纳闷为什么自己的网站老是优化不到搜索引擎
首页,更不用说进首页前三了,那么网站优...
</p>
</div>
</li>
<li>
<div class="news_date" l>
<i>09</i>
<span>Jan</span>
</div>
<div class="news_text" l>
<h3><a href="#">网站排名进入前三的技巧说明</a></h3>
<p>有很多客户都会纳闷为什么自己的网站老是优化不到搜索引擎
首页,更不用说进首页前三了,那么网站优...
</p>
</div>
</li>
</ul>
</dd>
</dl>
</div>
<div id="foot" class="container-fluid">
<div class="container">
<p class="l">Copyright 2006-2014 Bowenshangmei Culture All Rights Reserved</p>
<div class="r">
<a href="#">Home</a> | <a href="#">About</a> | <a href="#">Portfolio</a> | <a href="#">Contact</a>
</div>
</div>
</div>
</body>
</html>