当前位置:Gxlcms > html代码 > :before和:after伪元素的常见用法总结_html/css_WEB-ITnose

:before和:after伪元素的常见用法总结_html/css_WEB-ITnose

时间:2021-07-01 10:21:17 帮助过:25人阅读

1. 利用content属性,为元素添加内容修饰:

1) 添加字符串:

使用引号包括一段字符串,将会向元素内容中添加字符串。栗子:

a:after { content: "after content"; }

2) 使用attr()方法,调用当前元素的属性的值:

栗子:

a:after { content: attr(href); }a:after { content: attr(data-attr); }

3)使用url()方法,引用多媒体文件:

栗子:

a::before { content: url(logo.png); }

4) 使用counter()方法,调用计时器:

栗子:

h:before { counter-increment: chapter; cotent: "Chapter " counter(chapter) ". " }

2. 清除浮动:

.clear-fix { *overflow: hidden; *zoom: 1; }.clear-fix:after { display: table; content: ""; width: 0; clear: both; }

3. 特效妙用:

// CSS代码a {    position: relative;    display: inline-block;    text-decoration: none;    color: #000;    font-size: 32px;    padding: 5px 10px;}a::before, a::after {     content: "";  transition: all 0.2s;}a::before {   left: 0;}a::after {   right: 0;}a:hover::before, a:hover::after {   position: absolute;}a:hover::before { content: "\5B"; left: -20px; }a:hover::after { content: "\5D"; right:  -20px; }// HTML代码我是个超链接

4. 特殊形状的实现:

举个栗子:(譬如对话气泡)

// CSS代码.tooltip {    position: relative;    display: inline-block;    padding: 5px 10px;    background: #80D4C8;}.tooltip:before {    content: "";    display: block;    position: absolute;    left: 50%;    margin-left: -5px;    bottom: -5px;    width: 0;     height: 0;     border-left: 5px solid transparent;    border-right: 5px solid transparent;    border-top: 5px solid #80D4C8;}// HTML代码
I'm a tooltip.

人气教程排行