JSFiddle - React, Tailwind, and code Playground

HTML

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
        "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
    <meta http-equiv="Content-Type" content="text/html; charset=gb2312" />
    <script type="text/javascript" src="js/prefixfree.min.js"></script>
    <title>用css3实现鼠标移进去当前亮其他变灰</title>
</head>
<style type="text/css">
    *{margin: 0;padding: 0;font-size:12px;}
    .wrapper{border: 1px #708090 solid;width: 900px;margin: 100px auto;height: 300px;padding: 20px;border-radius: 8px;box-shadow: 2px 2px 6px #666,-2px -2px 6px #666;}
    li{list-style: none;}
	.box:hover li{opacity:0.2; }
    .box li{float: left;width:48px; height:48px;position:relative; margin-right:10px;
	 -webkit-transition: opacity 1s ease-in-out;
       -moz-transition: opacity 1s ease-in-out;
        -ms-transition: opacity 1s ease-in-out;
         -o-transition: opacity 1s ease-in-out;
            transition: opacity 1s ease-in-out;
	}
	.box li:hover{opacity:1; }
	.box li a{position:absolute;left:-10px;width:80px;height:30px;top:-30px;color: #fff;font-weight:bold;background:#000;border-radius:8px;box-shadow:1px 0 2px #fff inset;text-align:center;opacity:0;
	-webkit-transition: opacity 1s ease-in-out;
       -moz-transition: opacity 1s ease-in-out;
        -ms-transition: opacity 1s ease-in-out;
         -o-transition: opacity 1s ease-in-out;
            transition: opacity 1s ease-in-out;
	}
	.box li:hover a{opacity:1; top:-30px;}
	.delicious { background-image:url("http://images.cnblogs.com/cnblogs_com/hxh-hua/478335/o_delicious.png"); }
    .digg { background-image:url("http://images.cnblogs.com/cnblogs_com/hxh-hua/478335/o_digg.png"); }
    .facebook { background-image:url("http://images.cnblogs.com/cnblogs_com/hxh-hua/478335/o_facebook.png"); }
    .flickr { background-image:url("http://images.cnblogs.com/cnblogs_com/hxh-hua/478335/o_digg.png"); }
    .linkedin { background-image:url("http://images.cnblogs.com/cnblogs_com/hxh-hua/478335/o_flickr.png"); }
    .box...

CSS

.item {   
    height:200px;
    width:200px;
    background:red;
    -webkit-transition: opacity 1s ease-in-out;
       -moz-transition: opacity 1s ease-in-out;
        -ms-transition: opacity 1s ease-in-out;
         -o-transition: opacity 1s ease-in-out;
            transition: opacity 1s ease-in-out;
    float:left;
    margin-right:10px;
}

.item:hover {
    zoom: 1;
    filter: alpha(opacity=50);
    opacity: 0.5;

}