Home > Article > Web Front-end > Guide to centering web page elements_(4) Use CSS3 attributes to center elements horizontally and vertically_html/css_WEB-ITnose
Flex achieves perfect centering of sub-blocks
The parent block uses the display:flex attribute, and the sub-block margin can be adaptively implemented
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<!DOCTYPE html><html lang="zh"><head> <meta charset="UTF-8"> <title>块状元素垂直居中(已知高度)</title> <style> *{margin: 0;padding: 0;} .parent{ display: flex; height:500px; background: #03A1FA; } .child{ width: 100px; height: 100px; margin: auto; background: #BB3713; } /* 这个依赖于设置“margin”值为“auto”值,自动获取伸缩容器中剩余的空间。所以设置垂直方向margin值为“auto”,可以使伸缩项目在伸缩容器的两上轴方向都完全集中。 */ </style></head><body> <div class="parent"> <div class="child">ff</div> </div></body></html>Horizontal and vertical centering of unknown width and height elements
Use the transform:translate attribute to adjust
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<!DOCTYPE html><html lang="zh"><head> <meta charset="UTF-8"> <title>块状元素水平垂直居中(未知宽高)</title> <style> *{margin: 0;padding: 0;} /*简易版reset,工作环境不推荐使用*/ #container{ position:absolute; top:50%; left:50%; -webkit-transform: translate(-50%,-50%); -ms-transform: translate(-50%,-50%); -o-transform: translate(-50%,-50%); transform: translate(-50%,-50%); background-color: #A4FF00; color:rgb(33, 172, 134); } /*因为不知道宽高度,所以主要用translate属性拉回未知元素XY轴上的位置实现居中*/ /*若是单纯实现未知高度的元素居中,只要用到transform:translateY(-50%)即可实现*/ </style></head><body> <div id="container">Lorem ipsum dolor sit amet, consectetur adipisicing elit. Recusandae obcaecati expedita ducimus, rem laborum veniam qui quo facilis enim. Repellat blanditiis nemo, magnam, sequi illum perferendis consequatur modi maiores quaerat?</div></body></html>flex implements horizontal and vertical centering of the page
Define the justify-content and align-items attributes of the parent element of the centered element Just set it to center, you need to set enough height, otherwise there will only be a horizontal centering effect
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<!DOCTYPE html><html lang="zh"> <head> <meta charset="UTF-8"> <title>flex实现子块的完美居中</title> <style> * { margin: 0; padding: 0; } .parent { display: flex; justify-content: center; align-items: center; height:900px; background: #03A1FA; } .child { width: 100px; height: 100px; background: #BB3713; } </style> </head> <body> <div class="parent"> <div class="child">啦啦德玛新亚</div> </div> </body></html>