Set elements to be centered (front-end interview questions)

Center horizontally

Inline elements
Set text-align: center
block-level element
1. First define a width and height, and then center according to the left and right movement of the margin
2. Use the four properties of absolute positioning to center and margin: auto;
3. Use absolute positioning, then Set the value of left top to 50%, and use
transform:translate(-50%,-50%);
4.The elements in the play need to be set to display:inline-block; then its parent element is set to text-aligin:center ;
5. By setting float
6. Setting flexible layout
display: flex;
justify-content: center

Center horizontally and vertically

1.弹性布局,为父元素设置
			display:flex;
		  justify-content:center;
		  align-items:center;
2.position定位
		父元素设为fixed,上下左右都为0,margin设置为auto。子元素设为fixed,上下左右都为0,margin设置为auto。
position: fixed;
		top: 0;
		right: 0;
		left: 0;
		bottom: 0;
		margin: auto;
3.使用绝对定位

```html
/*此方法是在给定宽高的情况下;*/
	.one{
		width: 200px;
		height: 200px;
		background-color: lightblue;
		position: absolute;
		left: 50%;
		top: 50%;
		/*margin: -100px 0 0 -100px;*/
		transform:translate(-50%,-50%);
	}
	4.父元素设置display:relative,子元素设置display:absolute;上下左右都为0,margin设置auto
	

```html
<!DOCTYPE html>
<html>
<head>
	<title></title>
</head>

<body>
<div class="one">
	<div class="two">
		
	</div>
</div>
</body>
<style type="text/css">
	
	.one{
		width: 200px;
		height: 200px;
		background-color: lightblue;
		position: relative;
		
	}
	.two{
		width: 100px;
		height: 100px;
		background-color: red;
		position: absolute;
		top: 0;
		right: 0;
		left: 0;
		bottom: 0;
		margin: auto;
	}
</style>
</html>
5.父元素设置display:flex;子元素margin:auto
<!DOCTYPE html>
<html>
<head>
	<title></title>
</head>

<body>
<div class="one">
	<div class="two">
		
	</div>
</div>
</body>
<style type="text/css">
	
	.one{
     
     
		width: 200px;
		height: 200px;
		background-color: lightblue;
		

		display: flex;
		
	}
	.two{
     
     
		width: 100px;
		height: 100px;
		background-color: red;
		
		margin: auto;
	}
</style>
</html>

Guess you like

Origin blog.csdn.net/weixin_49549509/article/details/107774989