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<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>相对定位</title>
<style>
.box1 {
width: 200px;
height: 200px;
background-color: lightblue;
position: relative;
left: 200px;
top: 0;
}
.box2 {
width: 200px;
height: 200px;
background-color: lightgreen;
}
.box3 {
width: 200px;
height: 200px;
background-color: lightcoral;
position: relative;
left: 400px;
top: -200px;
}
.box4 {
width: 200px;
height: 200px;
background-color: lightgrey;
position: relative;
top: -200px;
left: 200px;
}
</style>
</head>
<body>
<div class="box1"></div>
<div class="box2"></div>
<div class="box3"></div>
<div class="box4"></div>
</body>
</html>点击 "运行实例" 按钮查看在线实例
<!doctype html>
<html>
<head>
<title>4种元素的对齐方案</title>
<meta charset="utf-8">
</head>
<body>
<div class="box1" >
<a href="https://www.baidu.com">baidu</a>
</div>
<div class="box2">
<span>我是一个行内文本</span><br>
<span>我是一个行内文本</span>
</div>
<div class="box3">
<div id="child">块元素</div>
</div>
<div class="box4">
<ul>
<li><a href="">1</a></li>
<li><a href="">2</a></li>
<li><a href="">3</a></li>
<li><a href="">4</a></li>
<li><a href="">5</a></li>
</ul>
</div>
<style>
/*1. 子元素是单行行内元素: 如a, span
a:水平居中: 在父元素应用: text-align: center;
b:垂直居中: 在行内子元素上设置行高与父元素等高: line-height:200px;
*/
.box1{
color:white;/*在这个地方设置字体颜色没用*/
width:200px;
height:200px;
background:black;
text-align:center;/*水平居中*/
}
.box1 a {
line-height:200px;/*垂直居中*/
color:white;
}
/*2 子元素是多行的行内元素：
a:水平居中: 在父元素应用: text-align: center;
b:垂直居中: 在父元素: display:table-cell;*/
.box2{
color:#FFD801;
width:200px;
height:200px;
background:#F62217;
text-align: center; /*水平居中*/
display:table-cell;
vertical-align: middle; /*垂直居中*/
}
/*3 子元素是块元素
a: 水平居中: 子元素设置左右外边距自动适应容器margin: auto;
b:垂直居中: 在父元素: display:table-cell;*/
.box3{
color:#FF00FF;
width:200px;
height:200px;
background:#FAAFBE;
display:table-cell;
vertical-align: middle;/*垂直居中*/
}
.box3 #child{
width: 100px;
height: 100px;
background:red;
color:black;
margin:auto; /*水平居中*/
}
.box4 {
width: 200px;
height: 200px;
background-color: lightblue;
text-align: center; /*水平居中*/
display: table-cell;
vertical-align: bottom; /*位于底部*/
}
ul {
margin: 0;
padding-left: 0;
}
.box4 li {
display: inline; /*将块元素转为行内元素*/
}
</style>
</body>
</html>点击 "运行实例" 按钮查看在线实例
<!DOCTYPE HTML>
<HTML>
<HEAD>
<TITLE>盒子模型基本要素</TITLE>
<meat charset="utf-8">
</HEAD>
<body>
<div class="box1">我是第1个盒子</div>
<div class="box2">我是第2个盒子</div>
<div class="box3">我是第3个盒子</div>
<div class="box4">我是第4个盒子</div>
<style>
.box1{
width:200px;
height:200px;
color:red;
background:black;
/*padding-top:10px;
padding-right:30px;
padding-bottom:20px;
padding-left:20px;*/
padding:10px 30px 20px 20px;
/*border-top-width:5px;
border-top-color:red;
border-top-style: solid;*/
border-top:5px solid red;
border-right:5px dashed red;
border-bottom:5px solid red;
border-left:5px dashed red;
/*margin-top:10px;
margin-right:20px;
margin-bottom:30px;
margin-left:40px;*/
margin:10px 20px 30px 40px;
}
</style>
</body>
</HTML>点击 "运行实例" 按钮查看在线实例
