1.块级元素和行内元素
2.水平居中和垂直居中
3行内元素的水平居中
1.table
2.设置line-height
3.text-align:center
4.margin:0 auto;
5.绝对定位
6.flex弹性盒模型
7.calc
8.auto
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<style>
*{
padding: 0;
margin: 0;
}
/*方式1：display:table实现居中*/
#div1{
width: 400px;
height: 400px;
border: 1px solid #000;
display: table;
margin-left: 100px;
}
#div1 p {
width: 100px;
height: 100px;
display: table-cell;
vertical-align: middle;
text-align: center;
}
/*方式1：text-align: center;line-height实现居中*/
#div2{
width: 400px;
height: 400px;
border: 1px solid red;
text-align: center;
line-height: 400px;
margin-left: 100px;
}
#div3{
width: 400px;
height: 400px;
border: 1px solid blue;
margin-left: 100px;
position: relative;
}
/*绝对定位实现居中*/
#div3 p{
width: 100px;
height: 100px;
position: absolute;
left: 50%;
top: 50%;
background-color: #4CAF50;
margin-left: -50px;
margin-top: -50px;
}
/*弹性盒子实现居中,推荐使用这个方法*/
#div4 {
width: 400px;
height: 400px;
border: 1px solid green;
display: flex;
margin-left: 100px;
justify-content: center;
align-items: center;
}
#div5{
width: 400px;
height: 400px;
border: 1px solid purple;
margin-left: 100px;
position: relative;
}
/*绝对定位之---calc实现居中*/
#div5 p{
width: 100px;
height: 100px;
position: absolute;
left: calc(50% - 50px);
top:calc(50% - 50px);
background-color: yellowgreen;
}
#div6{
width: 400px;
height: 400px;
border: 1px solid deeppink;
margin-left: 100px;
position: relative;
}
/*绝对定位之---上下左右等于0实现居中*/
#div6 p{
background: yellowgreen;
position: absolute;
width: 100px;
height: 100px;
top: 0;
bottom: 0;
left: 0;
right: 0;
margin: auto;
}
#div7{
width: 400px;
height: 400px;
border: 1px solid deeppink;
margin-left: 100px;
position: relative;
}
/*绝对定位之---上下左右等于0实现居中*/
#div7 p{
background: red;
position: absolute;
width: 100px;
height: 100px;
top: 50%;
left: 50%;
transform: translate(-50%,-50%);
}
#div8{
width: 400px;
height: 400px;
border: 1px solid deeppink;
margin-left: 100px;
position: relative;
}
#div8 p{
width: 100px;
height: 400px;
margin: 0 auto;
background: red;
}
</style>
<body>
<div id="div1"><p>居中1</p></div>
<div id="div2">居中2</div>
<div id="div3"><p>居中3</p></div>
<div id="div4"><p>居中4</p></div>
<div id="div5"><p>居中5</p></div>
<div id="div6"><p></p></div>
<div id="div7"><p></p></div>
<div id="div8"><p></p></div>
</body>
</html>