CSS 居中问题探讨_html/css_WEB-ITnose
前言
CSS居中一直是一个比较敏感的话题,为了以后开发的方便,楼主觉得确实需要总结一下了,总的来说,居中问题分为垂直居中和水平居中,实际上水平居中是很简单的,但垂直居中的方式和方法就千奇百怪了。
内联元素居中方案
水平居中设置:
-
行内元素设置 text-align:center;
-
Flex布局设置display:flex;justify-content:center;(灵活运用)
垂直居中设置:
-
父元素高度确定的单行文本(内联元素)设置 height = line-height;
-
父元素高度确定的多行文本(内联元素)a:插入 table (插入方法和水平居中一样),然后设置 vertical-align:middle;
b:先设置 display:table-cell 再设置 vertical-align:middle;
块级元素居中方案
水平居中设置:
-
定宽块状元素设置 左右 margin 值为 auto;
-
不定宽块状元素a:在元素外加入 table 标签(完整的,包括 table、tbody、tr、td),该元素写在 td 内,然后设置 margin 的值为 auto;
b:给该元素设置 displa:inine 方法;c:父元素设置 position:relative 和 left:50%,子元素设置 position:relative 和 left:50%;
垂直居中设置:
-
1.使用position:absolute(fixed),设置left、top、margin-left、margin-top的属性;
.box{ position:absolute;/*或fixed*/ top:50%; left:50%; margin-top:-100px; margin-left:-200px;}
-
2.利用position:fixed(absolute)属性,margin:auto这个必须不要忘记了;
.box{ position: absolute;或fixed top:0; right:0; bottom:0; left:0; margin: auto;}
-
3.利用display:table-cell属性使内容垂直居中;
.box{display:table-cell;vertical-align:middle;text-align:center;width:120px;height:120px;background:purple;}
-
4.使用css3的新属性transform:translate(x,y)属性;
.box{ position: absolute; transform: translate(50%,50%); -webkit-transform:translate(50%,50%); -moz-transform:translate(50%,50%); -ms-transform:translate(50%,50%);}
-
5.最高大上的一种,使用:before元素;
.box{position:fixed;display:block;background:rgba(0,0,0,.5);}.box:before{content:'';display:inline-block;vertical-align:middle;height:100%;}.box.content{width:60px;height:60px;line-height:60px;color:red;
-
6.Flex布局;
.box{ display: -webkit-box; display: -webkit-flex; display: -moz-box; display: -moz-flex; display: -ms-flexbox; display: flex; 水平居中 -webkit-box-align: center; -moz-box-align: center; -ms-flex-pack:center; -webkit-justify-content: center; -moz-justify-content: center; justify-content: center; 垂直居中 -webkit-box-pack: center; -moz-box-pack: center; -ms-flex-align:center; -webkit-align-items: center; -moz-align-items: center; align-items: center;}
结语
楼主暂时掌握了这些居中方法,读者如果还有好方法或是觉得那个地方不对,欢迎评论,不吝感谢。

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